This DIY approach you suggest should end at difficulty selection screen and the game maker should ensure it. 1) Unlimited potions (especially str pot on str dump char with tavern brawler) (abuse w/e) should not exist atleast in thier portrayed hardest mode. 2) Merchant should not have readymade potions in their infinitely refreshing inventory. 3) Player should buy ingredients/recipes and be challenged by medicine checks whether they succeed or not and transmutation dips to benefit from rolls above 15. (Maybe i'm suggesting a mechanic from a game other than a 5e game but u know what i mean) 4) Alchemy doesn't feel like a money dump in any way, sort or form but is a means to abuse!! Imagine a durge transmutation wizard with experise in medicine printing money selling potions. A lot of gameplay missed for a goty game. I wont even mention things like warding bond gale or barrelmancy which qre pretty irrelevant for first run standards. No crafting in general.
I might be hammering on alchemy alone ( as if I'm roleplaying a transmutation wizard from 5e lands who landed into bg3 world and found it broken) but the economy honestly feel relevant only when you are playing a wizard; in a 'pokemon- esque' gotta scribe em all adventure.
