That's cool. Yeah MBC1 style switching is much easier to deal with than MBC5 :) Most of my needs for bankswitching come from asset loading but I have had to resort to placing screen manager code in other banks for safety as I'm down to ~3k left in bank 0 with a few more fetures to add and possibly extern into other banks. It's fun experimenting with how to use bankswitching in general though.
Best of luck with your entry fanzy flani, looking forward to playing through it!