Thanks so much for the feedback!
In-game control help is a good idea, I'll look into it. The character switching is a bit tricky since the left/right arrows are used to change pages between equipment, spells, etc., so switching characters needs different keys. Maybe pgup/pgdn could work for this since they're close to the arrow keys. At one point during development I did have numbered shortcuts - I can't remember if there was a reason I removed them. I'll take another look.
Input rebinding is on my to-do list, so that should make things easier once it's ready.
Let me know if you complete the game (or if you have already), I'd love to hear your final thoughts.