I was curious, so I dug around. There is a post in
this thread (#6 by daremetoidareyo) which lists all PrCs with caster level progression.
I counted 107 PrCs with full progression. Not that 3.5 was bloated, or anything.
Good find!
Post 6? 86 10/10 entries, 29 5/5 ones, and one 7/7? That double counts a few though as things like the arcane hierophant is listed as 10/10 for both arcane and divine (also Fochlucan lyricist, mystic theurge, and true necromancer).
Also a bunch of these require giving up caster levels to meet the prerequisites for meeting the class like Arcane Trickster.
Still that leaves a lot of full caster ones and this list looks like it is from a lot more WotC sources than I had.
I remember being less than impressed with the power potential of the 10/10 candle caster from
3.0 Tome & Blood, a bit more so with the 10/10 alienist and their pseudonatural theme replacing fiendish/celestial on summoned stuff but not a big power bump overall. Mage of the Arcane Order was fairly meh, some minor bumps with only the hassle of the prereqs. Arcane Trickster and True Necromancer were 10/10 but gave up caster levels before entering the class. The eight others were not full caster prestige classes. Stuff like the Blood Magus and Acolyte of the Skin and Spellsword had a bunch of non-casting levels at 5/10 each.
I remember Incantatrix from an FR sourcebook being discussed as a big straight power up if you took it.
Given the varied design of prestige classes it was also possible to game them to take just the levels of a class that gave full caster levels and benefit from the bonuses they gave in addition. So the Elemental savant gave full casting for levels 1-9 but not for its capstone level 10, so it was possible to get nine full caster levels out of it and go back to normal wizard or a different prestige class after that.
I think the only full caster prestige classes I took were the 3.0 5/5 harper mage and the 3.5 10/10 loremaster which were basically wizards with bardic knowledge, four skill points a level, and few minor knick knacks.