Long dormant poster contribution:
For context, I mostly play heavy tanks, though I've diversified recently into the Brit armored TD line and am working on getting the Obj 430.
I've learned to despise Prok in any kind of slow tank because there's almost always one arty and going mid means you will be exposed and be targeted, and will eventually be hit. It's especially cruel to the AT-7 because the sheer number of ridges everywhere makes it impossible to return fire from the 1-2 line without cresting and getting chewed up as the gun is so low on the chassis. Prok is great fun in an ELC, a Bishop, or FV304, but I wouldn't want to inflict it on anything not capable of hitting and sustaining 40km/h on a flat surface. Black Prince, for example (The stock BP spawning on Prok singlehandedly tanked my recent WN from over 1.6k to whatever it is right now)
Mountain Pass is terrible for reasons everyone has already covered.
Airfield is a pain because artillery has basically free reign over the entirety of the map and if either high point is lost you can't advance without getting shot to bits.
Live Oaks is situationally bad, usually when one side has way more mediums than the other, at which point they just steamroll the south side and chew everything up before the heavies even get to town. Other times the south spawn will spot a few light tanks and everything grinds to a halt in the plain just north of the spawn, yielding all of town to north spawn.
Himmelsdorf is nigh impossible with the slower thin-skinned TDs like the Archer (it's inflexible enough already) and S35CA, as the map is so tiny camo can't really hide you and your mobility isn't enough to take advantage of changes in the situation. It's also really annoying to be a bottom tier slow heavy for similar reasons.
Westfield is usually okay, but having arty seriously puts a damper on what you can do in tanks like the T34.
Sand River is always murderous on slow, gun depression poor heavies like the Churchills and the KV-4. There's nowhere you can go that's really arty safe, and trying to fight over the ridges is a fool's errand when your turret face is weak and you can't depress the gun enough to hit the enemy anyways.
Fisherman's Bay is a fine map, it's just the sheer number of trees in some areas of the city makes it impossible to see where the fuck you're aiming or driving in arcade mode, which has caused more than one unfortunate permatracking for me.