Lanefan
Victoria Rules
Having all the class abilities baked in, such that the only real choice is choosing one's class once at roll-up, is fine; and makes levelling-up a snap.It's not so much about "mechanically the same underneath" as "How they grow in power and ability is entirely predetermined by choices they made a long time ago".
Sad to think this isn't the goal for all editions; that the character mostly grows through what it does in play, and maybe in ways other than purely game-mechanical.This is different in 1e because 90% of your power comes from Loot, whether it's your fighter's arsenal or your wizard's spells found. In 1e how they grow is determined by what they've done
Items can be another good character differentiator, to be sure, once said characters have been at it long enough to acquire said items.
Not every DM allows this sort of thing.(until you give Job the Fighter all of his elder brother Rob's old gear, much of which which he inherited from his elder brother Bob).

To its detriment, says I.But 5e deprecates magic items and loot.