So you didn't realize this until 4e? Or you couldn't help yourself, and 4e solved the problem by removing the options?
No, I realized this earlier. Though the Iron Heroes Villain Classes helped me realize it even more.
I'm still not seeing the evolutionary leap to 4e.
Maybe you're not looking hard enough?
Or maybe it just doesn't exist. It's a gradual change, and it's not like 4E is reinventing role-playing.
But I think it is a leap to go from a more "explorative" creature building approach to a goal-oriented one. (But I wouldn't call it an "evolutionary" one).
My goal is to provide a challenge for my PCs at level X. I want thematic elements Y,Z, and represent them with special abilities of the monster. I just set the level, and have all the basic data I need. The real work is fleshing out the thematic elements.
The "explorative" approach in 3E to me is that I still want to get to level X and thematic elements Y and Z, but I have to play around with monster type, HD, skill point distribution, ability score placement and then a lot of guessworking on whether I achieved the level X, and only then I add the thematic elements Y,Z in.
Am I doing something wrong when I play 3e monsters right out of the SRD? Are they not fun? What if I (gasp) change them on the fly-- say, arbitrarily double their hit points halfway through combat? If I say YES! to my 3e players when they want to try something not codified into the rules... is this in error without the DMG explicitly granting me permission to do so?
Of course you are doing something wrong. My way is the only correct one.
Arbitrarily doubling hit points mid-combat feels like "cheating" to me. I am willing to do it before combat (I did - I created my own Minion, Elite and Solo templates for my Iron Heroes campaign), but halfway in? Might do it, if I really feel that it's worth it. But I don't feel comfortable with it.
And doing something not codified in the rules - I can do that, usually informed by RAW. But outright ignoring the rules? I'll try to avoid that. (And why did I get this rulebook if I want to ignore the rules anyway?)
The reason why I often did not use 3e monsters is because they didn't fit the levels of the PCs, or I just didn't like them, or because I wanted to give a monster or NPC with a unique flavor. I needed tools to build my own monsters, because I am not always happy with the existing ones. Sometimes, I am just a special snowflake.
One of the most satisfying adventures for me was when I build an adventure around "spider & crystals". I created templates, a few monsters and NPCs with the template, and also a unique "crystal spider" monster, featuring abilities of various Spiders, and with crystal-related powers.
I think the resulting monster was probably very close to a 4E monster - simple rules, but enough abilities to be memorable.
If I wanted to run a simple encounter against, say, Goblins - I had to write up different Goblins, because otherwise, they would all look the same and the adventure needs to be over in two encounters, or the players - and the DM - are bored.
Sure, I could have added several other monsters - but I didn't want to run a "Goblins with a Zoo" adventure, I wanted to run an adventure with Goblins.