A new entry to Jay Barnson's Tales of the Rampant Coyote blog briefly covers the character creation and development system in a handful of CRPGs, including the Wizardry, Realms of Arkania, and Fallout series.
CRPG's based on the AD&D rules have their own characteristics. When you see AD&D on the box you know a challenge awaits. It took me a while to get used to the fact that the stats were almost set in stone after creation with a few exceptions at certain levels. I had gotten used to Wizardry 7 giving me some options at each level, and Realms of Arcania giving me a pile of paperwork to fill out at each level. But there is a certain amount o allure to these games. On the surface the stats are simple to roll and edit, but the consequences of your choices are very advanced when weighed against the other choices made concerning the character. For this system I would have to say that the character classes are my favorite part. Each one is so detailed and interesting, and while some are disappointing when battle tested, their presence and lore is still very inviting. I'd say that the character creation/progression system in the Wizardry series has had the most impact on me. Sir-tech really earned my respect for never "dumbing them down" and properly evolving the systems over the course of eight games.
Fallout shares some characteristics of AD&D, but feels very different. The skills were fun, and the set in stone stats were a challenge to tweak out right. The stats were made even more enjoyable because they were so directly tied in with the strategy combat present in the game. It didn't take much adventuring to realize your character can't keep up with your game play style. In fact, it probably took many of use a few characters before we really had a (good) character to play. To top it all off, the perks were just cool from the name to the effect. For instance, (Bloody Mess) sounds pretty cool, and quite honestly it was. :)