There's a new map that's been added to the Official KOTH rotation. Can't remember the name, but it's got a bunch of buildings with Japanese paper walls and the like. The control point's building is very small, and it has one screen on both the RED and BLU side. Basically, it's very close quarters.
I went with the Revengineer build (Frontier Justice + Gunslinger) and found out I could do extremely well.
Then I went with Jag and Stock Shotgun.
I found myself in second or third place.
Note: I've also noticed that my skill with the shotguns is much greater than before.
My sniping is still extremely weak, so I'm unable to live up to the monkier "Crazed Gunman".
That sounds like koth_suijin, a rather fun and pretty map. I'm glad it was added to official rotation, these days it's fairly well balanced.
Also, the shotgun is a VERY good weapon, especially on engi: a stock shotgun engineer is essentially a slower moving scout without a double jump. Engi shotgun aim feeds into Scout scattergun aim and vice versa; they're fairly similar playstyles, being both short, annoying 125hp shotgundudes. Of course, yes, scout has other things, and Engi has his wrench and such, but take away their class unique ability, and scout and engi are identical besides a slight speed boost on the Scout.
So I guess what I'm trying to say is that Engineer is surprisingly deadly if you play aggressively.