I do love that two people have posted about how important having different mechanics and different feels is to them.
I can't help but agree.
"Build" and "gimmick" aren't exactly the same. Once upon a time, there was a... league... that allowed characters to enter with one chachka, one bit of substance-free style. Like a pipe. Or an abacus. Or a harp pin? It was a way to give your character a gimmick, but required no real build skill.
OTOH, there's lots of build skill involved in the code I write... but I wouldn't say that my code has a "gimmick".
I think that it's valuable to an RPG - perhaps especially a flagship RPG - to allow players to stretch their Build muscles if they so desire, and for characters to be able to have gimmicks. But I'm not sure I see those as inherently related. I guess one could try to argue that they're better when they are (or can be) related?
(evil anime glint) Oh, no, that's a perfect example. Two reasons.
1) I had a group of friends who'd get together periodically and run LAN parties (and, occasionally, RPGs or other activities). Getting people to play the big game(s)? Easy. Other games? "But nobody has that installed". Also learning curve issues. A much harder sell.
2) One of these great LAN games was (IIRC) Unreal Tournament. UT had some "standard" mods, like Runes and Relics, that did things like give the character who had them extra speed, or extra damage, or take less damage, or vampiric damage, or self destruct when killed. But there were lots of mods to UT. One of my friends hosted a game with some of their preferred mods. The way the game worked, it downloaded the foreign mods temporarily to play the game... but the game didn't wait on this download. Yeah, the match was over before anyone else finished downloading the missing mods... and then, when the next match started, the download process began again from scratch. Ugh.
Having a single format that everyone knows and uses is great. It means that the casual player only needs to learn 1 set of rules, purchase 1 deck, rig 1 set of weighted dice, come up with 1 character, learn 1 world history and set of lingo, install 1 app on their computer, whatever. It lowers the bar to entry for the casual gamer, and ensures that a group of friends who are into the hobby who get together have something they can do.
Unlike all the rules- and conceptual-downloading that would be necessary if a group of single-system casuals got together who had each played different games; say, Beer & Pretzels D&D, Mirror Shades Shadowrun, Plot-Driven The Dark Eye, and FATAL. They'd spend the whole session just trying to explain the game to fellow gamers without ever getting to play.
Ah, that's slightly different from the optimization perspective I was taking. I may try to recalibrate, or I may just stick with and be stuck with my momentum.