In order, considering utility given it's REQ cost:
- (Pre-nerf) L3 Grenade Launcher
- Void's Tear (amazing for vehicle and spartan suppression, especially at a narrow choke-point)
Yes, the Answer is very good, but not good enough at long-range vehicle suppression to make my top list. Nornfang is pretty much purely a "farming" REQ, not useful in a sweaty game except maybe for ONE person to call. Having multiple teammates calling a nornfang is just asking to get trip-capped.
Although with the recent nerf to the banshee, this list may change. Endgame and arclight won't be as crucial, and snipers (including the 'fang) will be better.