Firstly I am a huge fan of this map, great fun and a nice challenge (especially solo). That said, I really think the perk limit is a problem. The EMP crawlers are so difficult that PhD is a must have perk, and the sprinters and juggernauts mean you basically need stamin-up. This only leaves 2 perk slots which must be used (on solo) for quick revive and juggernog. So basically now I'm stuck with no speed, no double tap, no ammo-matic, no third weapon and now no thundergun. This makes it a lot less fun.
There are loads of ways you could alter the perk limit, random perk for beating jugggs, buy extra slots or just increase it to 5 or 6. Love the map but think something like this would be a big improvement.