Unfortunately, I didn't have time to read the comic about cats. Alas for me, because both the cat is cool and the idea is nice.

Comrade Lenin, you say? Yes, he is perfect for the role of a connecting link. Again, as a character comprehending the subtleties of the world in which he finds himself, he looks attractive. Well, and the play on words "Ilyich - the Lich", which works equally well in English and Russian :-)

А что, если пальнуть в зубы? Сколько там патронов, 6? Значит, ещё 5 раз бахнуть можно, если всё верно помню, и наган нигде не применялся.

An old barn full of mice! What could be better for a cat!

"Call me" is "Позови меня" in this case. Well, really, they won't use the phone ;-)

By the way, I hasten to note that your translation has become much better. Machine confusion has become much less common.

Creating a "new" species of aliens and working with them is not a problem. The main feature of aliens is intelligence. Intelligence is an energy-consuming thing, evolutionarily it is not as advantageous as just sharp teeth or long legs, and is needed when a creature has to adapt to a constant change in living conditions, learn to interact with the living and non-living environment outside the standard scenarios of "gnawed a bush", "gnawed the one who gnawed a bush", "drove off a competitor", "covered the offspring with himself" (oh, even here there is socialization of creatures comes, yes-yes). Hence, an approximate similarity in appearance and way of thinking is assumed for intelligent creatures. Even if the creature you create is significantly ahead of a human in development and, say, can think nonlinearly, processing several streams of information at once, it will have two main similarities with a human: it will adapt on the go and it will be socialized. And externally, conceptually, it will not differ from a human as much as we are sometimes shown: an intelligent octopus is much more bullshit than an intelligent catgirl or an intelligent vampire, for example. Because the possibilities for the development of an octopus are limited to life on the seabed, where its maximum is to settle in an old jug, instead of a crevice in the stones, continuing to grab fish swimming by with its tentacles. For effective survival, an octopus does not need to interact with either its relatives or the surrounding space, it does not even protect its eggs - there is no need. It just releases a bunch of eggs into a hole in the sand and swims on. Whereas the development possibilities of the ancestors of the catgirl and the vampire are much more diverse - they are forced to interact with an infinitely more complex environment than the "seabed", build more complex and versatile shelters, look for food, and most importantly - intensively interact with each other.
An alien, in order to become intelligent enough to move to the "civilization" stage, needs access to a variety of resources, and most importantly - the need and ability to interact with them. Therefore, it will be something on land, amphibious or semi-flying (here the difficulties with the brain begin: brains require a lot of energy, flight also requires a lot of energy, the resulting system is difficult to optimize, but possible), with functional limbs, vision, hearing, smell, and dense enough not to turn into amorphous jelly when trying to interact, say, with a log for building a shelter or the carcass of an animal to be eaten. Why is the catgirl bad for this? She is ideal for this! No less ideal than a large ape that evolved into a human.
Here, technically, it is even possible to justify the existence of a species consisting only of female cat-folk, or vampires, or martians, or any other creatures. Look, if the genetic apparatus allows them to mate with each other and produce viable offspring in the format "female + female = female", then males and hermaphrodites are automatically not needed for this species. And this is possible, if you dig even into human or cat genetics, it works. And parthenogenesis works. Here is a generally simple mechanism and the result can be better than in the bisexual one that we have. Fewer social difficulties, difficulties in finding a suitable partner, higher fertility. In the plot I'm working on, there's a fairly large and well-developed civilization consisting of only female lizards, and viviparous ones at that, and a kind of "mammal". True, at the next stage of development of a technocratic society, they delegated their reproduction to machines, but they did a pretty good job before that.
But for obvious reasons, this scheme won't work with males. Males cannot reproduce on their own purely physically, that is what makes them different. They do not have the appropriate set of organs and body functions for this. If you add them, they will be hermaphrodites, like worms or some types of fish. However, genetically, it is also possible to make a "male + male = male" scheme. Therefore, a conditional totalitarian-fascist regime, possessing a sufficient level of technology, can turn its people into space marines from Warhammer, assigning the function of reproduction to machines. In this situation, females are no longer needed, however, their presence in the basic configuration of the species is assumed here.
A species with three sexes is possible, but it risks not surviving long enough to gain intelligence. With four or more, it's pointless, since the reproduction process becomes so overcomplicated that it becomes inoperable. Whenever you overcomplicate things, you end up with a fucking Maus tank that might look cool, but doesn't work.
Whenever you invent a new species, use this simple rule: the species must be complex enough to be intelligent, and simple enough to "not trip over its own legs" and become a dysfunctional piece of shit, like that centipede from the fairy tale that forgot how to walk when asked how it managed not to trip over its own legs.
The main difficulty is to depict the culture of aliens, if you have undertaken to create a civilization for them. Here you can't get away with the maxim "it should be similar to us". Cultural aspects can be completely different, absolutely alien to ours. Therefore, if you don't want to become a xenoculturologist - just take a real existing or former culture, the same ancient Egyptians, medieval Japanese or some Aztecs, "refined" it a little to suit the needs of your aliens specifically and use it. A hackneyed technique, however, it always works without fail.

Subplots are not bad. You need to be able to maneuver between them and return to the main plot. Watch the local comic "The Dumbest Magician in the World" ( https://acomics.ru/~stvmm ) at your leisure - it has no English translation, but even from the pictures it is clear that the author maneuvers in the plot on the fly, going into subplots and emerging from them. The author does not disdain the most idiotic ways to get back on track when he starts to go in the wrong direction. But everything is built around specific characters there, yes: first there is the grandson - Gregor Stiepldorf, then the grandfather - Ulrik Stiepldorf, and all the subplots revolve around the characters who surround these guys. In your case, even though you deny it, the story is fixed on the Reaper and Katya, and there are also a number of secondary characters whose stories you know how to work with, which is clearly seen in F-y-T. When you start obsessing over secondary characters and NPCs, just ask yourself: "What's going on with Reaper and Katya now?" And then the story won't start to disintegrate, you won't have to restart it. Having a plan for future chapters is a great thing.

And don't try to make outright Science fiction. It limits your flight of thought when you start talking about Bastet, the harvest of souls and vampires. There, every nut needs a technical justification, which is easy to dive into like a swamp and drown. Just make fantasy-like fiction, like Star Wars. There are blasters, aliens, robots in place - that means everything is assembled, awesome. Ultimately, Star Trek also slipped into fantasy due to the difficulty of staying within the scientific framework, when the scriptwriters were required to justify a bunch of things they didn't understand and didn't bother to look for extra consultants.

Уж, пардонте, что под рукой было - то и надела. Лабутенов в местное сельпо не завезли-с.

ЗЫ: Опа, Аянами на аватарке! Ещё кто-то помнит?

Let's hope that with this reissue of the comic, things will go better for you, more cheerfully and joyfully. The new appearance of the characters has done good, you have already laid such a basis for the plot that oh-vey, all that remains is to firmly hold on to the rails and not fly off again under the derailment of side plots that appear along the way :-)
I am glad that you have not abandoned what you started and time after time try to bring it to perfection!
I will wait for the appearance of the Martian Queen, she has a very pleasant face, and, again, the introduction of aliens into the setting... I love fuckin' aliens, you know…$-)

BattleBeast ещё можно. Правда, ни те, ни те в сеттинг не особо вписываются. А ещё Disturbed, Amarantie и ещё хрен знает кого… ~_^ Но Мейки выбрал фолк-рок, и получилось вполне.