Are there "tons of other characters" mechanically?
Because we're down to three or four classes from the PHB in 5e. Fighter, barbarian, rogue, and possibly monk. Everyone has to be one of the three classes because all the other classes are spellcasters - and you also don't want Arcane Tricksters, Eldritch Knights, and Four Element monks (not that you want the latter anyway, but that's a mechanical issue).
You then have no healing magic to justify D&D's absurd hit point rules. You have no magic. Your combat is D&D Cinematic Combat with the absurd consequence-free hit points. And you've basically nothing tying you to the world.
If someone wants to run a game without spellcasters that's more than fine - there are plenty of games where you don't have roughly 40% of the player facing rulebook made up out of spells. If someone wants to do it using D&D rules that makes me seriously question their competence as a DM. It's like trying to use the claw on the hammer head as a screwdriver.