There are ways to get around that problem with the guns, for example if you got a humanoid sprite that doesn't wield weapons at all, or got them built in, or holds them in a way where overlapping aint an issue - as for the walking stuff, the game could simply switch out the models so it's just one (whole) model loaded in each frame, considering we got like 20 years of computer power over the original I don't think it would be much of a data sink
I did propose that the game have a switch for handling it one way or the other, so depending on what kind of asset you want to include it can be a lot less work involved. A bit like setting up a fancy Excel sheet, some extra work up front but you save time in the long run.
e: Ideally all the loading information for the model/frames would be editable in a simple .txt file or similar, so we can set exactly how Y-levels, load-orders of overlapping frames, number of total frames and their order etc should load for each individual folder/sprite.
Maybe it's not possible to go over a certain number of frames for an animation sequence due to how the game works but the other parts would really give some freedom!