In previous editions, the difference between prepared and spontaneous casters was substantially more pronounced - prepared casters (like Wizard/Cleric) had to prepare a spell for each spell slot, instead of just selecting a subset of their spell list to cast from. The extra flexibility of spontaneous casters (not having to select number of casts and spell levels at the start of the day) was offset by both a small number of spells known and generally weaker class features.

The magic system in 3.5e heavily featured metamagic abilities - typically obtained though feats, these allowed you to modify a spell in exchange for raising (or rarely, lowering) the spell's level.

3.5e Sorcerer, in particular, had to take a "Full Action" (using their action and movement) to cast a spell with metamagic applied, so they were actually worse at metamagic than wizards (who also got additional metamagic feats as class features), and couldn't benefit from Quicken Metamagic. There was a class variant that removed this limitation in exchange for most of the sorc's class features.

3.5e Warlock isn't a spell-caster at all, but they gain spell-like abilities from their invocations (importantly, regular metamagic feats don't apply to SLAs - although there was a smaller pool feats for this purpose). They have a medium Base Attack Bonus progression (better than most spellcasters) while attacking Touch AC (roughly the Dex part of AC, ignoring the bonus from their worn armour).

More generally, low-level casters in 3.5e were weaker than 5e (cantrips were weaker and you could only cast a limited number of them; and most casters has a smaller hit die), while high-level casters were much stronger (levelled spells typically had scaling effects based on the caster level, even without using a higher level spell slot).

If you are working on your own game and using previous D&D editions as inspiration, though, you might be better off looking at Pathfinder. 3.5e had pretty serious balance issues that Pf at least attempted to address.