Whew! Lots to unpack here so I'll try to work through and will probably stray into some random thoughts of my own!
So much of what you describe is very familiar to me as well. I'm very much the same in terms of the perfectionism, wanting to constantly redo things, etc. While I have a mind for worldbuilding I don't think I'm as focused on that as you are and am a little more willing to fly by the seat of my pants!
While having your character and world "bibles" fleshed out beforehand is great; I think it's just important to have a basic foundation or structure. I realize that the story arcs and settings I have loosely outlined at current will take years to come to fruition and entail thousands of hours of work in the interim. So while it's nice to have a map, you want to leave yourself room to wander. As you work you're bound to come up with better ideas and ways of handling those next issues and story arcs, so there's no need to set them in stone now. On a smaller level, that's even why I don't tend to do a tight dialogue script before I start working. It seems more efficient and natural to scribble dialogue notes and come up with that final scripting as I draw. Each page is a good 8-12 hours of art "busywork" when your mind can think about script and story so I find it best to lump that together!
Building my worlds too extensively beforehand also makes me prone to the mistake of trying to cram it all in. In some of my first drafts at my comic I had cutaway scenes in an effort to explain to the reader exactly what was happening, before I realized they were unnecessary and ultimately harmful. It worked out much better to cut that sort of exposition out, leave some questions unanswered, and allow the world to present itself to the reader at the same pace it was presenting itself to the viewpoint characters.
From what I've seen of your recent work I do believe you're ready to "just do it." Be as perfectionist as possible while still moving forward and then just make each page better than the one before, and each issue better than the last.
On the forward thinking and practical matters of publishing and getting it out in the world I'm not sure what differences there may be between the U.S. and U.K. markets, but I find it invaluable to go to conventions and pick the brains of the small artists and publishers there to find out what others are doing and think works, and then watch their paths develop. I've seen and interacted with several creators who one year will have a completely self published book through a small run printing company, and the next year are releasing that material through a small publisher that picked up their book, and another year or two on might be releasing a collected edition through a mid size publisher who found their stuff from the small publisher! I think the opportunities will present themselves as you start to get the work out there and the most important thing is just to be smart about any deals you do make and leave yourself the legal flexibility to go elsewhere or strike up additional partnerships.
Ithaqa than I am with my own work. I get to spout off theoretical nonsense and then see what happens when he puts it into practice! I think it's good to look at people like that who are at similar stages and see what you can learn and adapt from their workflows and publishing journey. In the next 6 months I should be seeing some significant forward momentum on my own comic project, and you can be sure I'll be sharing anything that works or fails here!I've joked with @drwatson that he's my "guinea pig" as there's been printers or distribution tactics I've mentioned and he's pursued because he's much farther along with his comic
And finally on the topic of Hive itself, I think the best thing to do is exactly what you're doing... just use it like a blog or any other social media and let the numbers do their thing in the background! Hopefully when you're ready to do some printing or marketing it'll give you some extra financial resources to throw at it. However if you have any specific questions or concerns, you can always reach out to me directly and pick my brain here or on other DMs like Instagram.
That's an unexpectedly detailed response, in a good way. I can always rely on you for valuable points of view!
Everything you've pointed out is pretty much the same areas I've been looking at. In terms of character and main plot, I have actually worked out a loose plot-line that can potentially span across 3-4 books (or "series/seasons" - because I love the idea of making an ongoing story) and already have several ideas for sub-plot, character arcs etc - although it's true what you said that a lot of those become more harmful and unnecessary (plus it overcomplicates things). I do like the idea of keeping things remaining a mystery though, it would work very well with the Enigma character (who is essentially mystery incorporated), but I am going to revise on what is needed and what can be dropped (or used later).
In terms of page scripting, I like to try and write out a full chapter (or issue) in combination with page layout drafts (with isn't exactly a norm, but it does help me work out a good arrangement of picture and text). I have the first chapter mostly worked out in terms of writing, my biggest problem is starting the story - that old cliche of "it's hard to begin but easy to keep going" - but I've recently brainstormed a very visually exciting beginning to the story (my theory being it should help capture the reader and make them want to see what happens next), usually all of these ideas are springboarded off my wife - who pretty much acts as my quality control guinea pig. If the story makes no sense, or the jokes don't exactly hit home with her, I tend to know that certain parts need tweaking.
I do remember you mentioning perfectionism a few times on your instagram posts, hopefully that doesn't cause as many problems for you either. Looking forward to seeing Zombies become a fully readable book, definitely interested in picking up a copy - if the story matches the quality of the artwork (which it will, I'm sure), it's going to turn out great - and the whole "colourful apocalypse" still stands out as a cool concept!