Well a lot of today was lost in umm'ing and arrr'ing but I made a little prototype progress before heading to bed!
I'm working in Pixel Game Maker MV as it's a visual scripting I can understand for basic game building. I've built a basic tile set for mapping and planning. I've also created a little submarine drone thingy.
I've toyed with some Chromatic Aberration which I may not keep, I'm gonna build up a vertical slice of map to test it on, see how it feels when in a full map chunk!
I toyed with the idea of setting the game in a Victorian Space Adventure to the moon using stuff like The Gene Machine and A Trip To The Moon as inspirations but I think it would be a much bigger task to do so. I'm not ruling it out, but based on how quick I end up making this prototype will decide if I have enough time to be more ambitious and expand the scope to something like that.