Just let me tell you some last things about that. Not to criticize what you say but I think there is no answer...
A map you know very well (one of your favs you often voted for) is a very good example : Sex Street.
Counterwise of what you just wrote, that one is NOT small but really good to play in run and gun mode.
And as I already said it depends of the number of players. You can hide and guide if there are few players on, trying to hide and guide themselves.
But if one (or some) good player is running/gunning, it's a really better way to show off and start to run and gun too !!! If HE IS GOOD, don't stay in or up to guide !!!
SO... IT DEPENDS...
EB uses to hide (not really hide) and guide, Darkmatter too (but sometimes not), they win sometimes...
YOU use to run and gun (like I myself do) and you win sometimes...
A noob try to hide and guide and... almost NEVER WINS !!!!
A noob with a few practice hours done, will try to run and gun and DON'T WIN cause he nukes himself more than the others do (and sometimes, if I'm not really concentrated on my "job" I DO explode myself more than anyone !!!
I think that what doesn't please you is when noobs, in small or medium maps, "run and hope" (like you're right to say) they happen to kill many people only because of the luck (even you and me and any good player).
I don't like that too much but it's a characteristic of our fav game so I think THAT IS a thing you don't like !!!! Am I right ?

And... I won't talk about that anymore... it's a real endless story...