I used to think min-maxxing was the issue, but then I rolled a 18 and a 17 once while building a character. I ended up with a min-maxer's wetdream when building a character.

The lesson I learned is that min-maxxing doesn't ruin the fun for anyone else.

Its the type of person who is inclined to min-max in the first place that I don't like playing with.

Which can translate to: If your entire build revolves around making it a certain type of hammer the odds are that you will go out of your way to find excuses to use that hammer.

I've noticed at times that the weaker/more balanced characters tend to be forced to think outside the box a lot more often and are thus more fun to play with.