The gameplay mechanic actually reminds me a lot of survivor games like vampire survivors, great stuff.
I personally don't really find an incentive to switch the mode gameplay, but I think it would be nice if there's some type of enemy that forced the need to switch the attack so player can experience more of the mode mechanic.
Also tips for art exporting for games: try to export as .png rather than .jpg even in things like title screen, if exporting as .jpg it'd be great if the noise can be set to none. Exporting as .png is much easier for it to be clean though. For character sprites, try to make them in similiar if not same size first so when they're resized the outlines for every character can stay consistent.
The game is certainly enjoyable, by the way! Keep up the good work!