I have to disagree with you on the map choice.
Poundamonium on Waterworks is far, far better.
I know a spot where you don't take any damage unless you let the FPs stack up. This spot doesn't work for Demolitions, but it's awesome for Firebug.
There's also another spot i know of, on Icebreaker. If you reach this spot you'd be really unlucky to take any damage, but on beginner it's not really a problem.
EDIT: Oh and Departed. I know of a spot where you take next to no damage, and can level firebug and berserker pretty well. Another spot on this map is an exploit and or glitch, which i won't go into detail about. Suffice it to say it takes the challenge out of the game.
All of those were basically exploits lol, and waterworks fails.... It has around 50+ ****ing exploits (exaggeration of course, but it has probally 5+ exploits)
Oh and all of those maps have serious exploits xD!!
P.S. IF you want to level up quickly, find some cool maps invite some friends and have fun..... You'd be amazed how fast leveling passes you by just simply hanging out! If not heres my guide of awesomeness:
*Sharpshooter: is the easiest perk to level up so you don't need a guide on that.
*Field medic: Just do your ****ing job as a medic xD you'll get stumped around level 5-6 but that usually defines how much of a medic you are

*Commando: Play KF-survival , I usually wouldn't tell you what map to play to level up but seriously.... Commando is a gay perk to level up >.< and this map gives a **** LOAD OF STALKERS.
*Bezerker: Hack stuff up. (Not as in programming >:O)
*Demo: Just throw your nades I actually got around 4m in around a week of playing just throwing grendaes.
*Firebug: You might have to play bloated for this one...... Or just burn things

*Support Specialist: you get the damage EASILY. Welding..... Just weld a ****load of doors xD (BIOTICS!??!!?!)