I quit D&D/D20 after 1e, and did not return until 5e.
I like 5e, but I was thumbing through the various editions which I had missed, and I was struck by the way it seemed to do more than 5es, especially in the way it allowed you to customize your character.
How was it in actual gameplay?
The biggest problem is that, in practice, there were
way too many skills for how many you could take. Most characters got 2 + Int mod skill points, which in practice meant you got two to three skills. 2-3 out of
36. And some of those skills (Knowledge, Profession, Perform, Craft) were further subdivided into multiple skills.
Overall there were two types of skills:
1. Skills that you benefited from getting as high as possible, or at least very high. Spot, Listen, Search, Stealth, Tumble, Use Magic Device, etc. A lot of them are opposed skills (where you and another character roll opposed checks.) In practice, you never really needed more than 10-13 ranks in a skill to always succeed, IMX. At that point with synergy and decent stats you could take 10 and get a 25 which is good enough for just about everything. In the meantime, characters with no ranks could virtually (or actually) never succeed on unskilled checks.
2. Skills that essentially had diminishing returns or that you only needed in order to get your Prestige class or only to get the synergy bonus (e.g., 5 ranks in Jump, you get +2 to Tumble). These skills you took to 5 or 8 ranks (level 2 or 5) and then switched to
anything else. Some of the meaner Knowledge skills are the most common ones in this category.
There were also lots of other minor issues.
Cross-class skills were
never worth it and always too expensive to bother with. Double cost plus capping out at half normal max ranks made them too expensive and too ineffective.
Lots of skills like Scrying, Decipher Script, Forgery, etc. were so rarely used that they essentially never came up. Most of those skills have rolled into another skill (e.g., Arcana) or have become tools in 5e.
Splitting Spot and Listen was an irritating dichotomy and almost never meaningful. 90% of the time, the thing you could spot you could also hear and vice-versa.
People had a hard time understanding Search vs Spot just like the do Investigate vs Perception. Lots of skills appeared to have significant overlap, which still continues (i.e., Persuasion vs Deception in 5e).
Use Magic Device and Tumble proved that if you want to give characters an ability useful in combat, you should just give them that ability straight up.