#to be clear by dnd I mean a d20 based adventure fantasy rpg

[owlbear33]

in this hypothetical heroic fantasy (or at least not a dungeon game) dnd

I have two big sticking points

the first is easy, how tactical grid combat friendly does this need to be, since 3e at least tactical grid combat has been a big, if optional, thing but like many OCRs ditch it, and frankly many games that I love, particularly exalted (from where I am taking much inspiration), use a series of range bands instead, usually some variant of close(5ft), short(30ft), medium(60ft), long(90ft), distant (don't bother) and it works fine, sometimes combat positioning gets a bit handwaved, but if the combat mechanics don't care too much about that it doesn't really matter, and there's the rub, do we want the combat mechanics to care about that

the other is magic, about which I have a few questions

since 4e at least (comments about various 3e/3.5 non-wizard classes) vancian casting has been diminished or nonexistent, and honestly I can't say I'm super bothered about that, it very much feels like an adaptation for the intense resource management of the dungeon crawl, and I've always felt risk management a more fun limit on magical power, or maybe something like the effort system used in assorted sine nomine games (more Godbound and SWN than WWN) a limit on how much you can maintain at once than do in a day

the other question is how many sorts of magic should there be? and how distinct should they be? as I understand it the OG made do with just the magic-user, but that quickly expanded to include clerics, druids, and all sorts there're all sorts of ways you could sort the different ways of doing magic in current dnd, but I've oft in the past argued they could be more distinct, the 5e warlock isn't a patch on the 3.5 one

in all honesty, if I had the time and energy for it (and were this not a thought experiment and was I actually seriously considering writing this game) I would write a whole bunch of different magic systems, from learned sorcery, pact and/or oath magic, divine blessings, and so on let GMs decide which are present in their worlds, it's not like all fantasy fiction uses the same magic, why should all dnd campaigns

all this brings us to the thorny issue of classes, they seem to be in fashion these days, though people call them playbooks, I've never been a massive fan, and if you have lots of different magic it may be better to have more freeform character building