I love Munitions Mastery as is. Every power but the Sleep Grenade can be highly effective in the right hands. Maybe that can too but I don’t use sleeps.
Surveillance is definitely the most meta-relevant reason to pick the pool. -res and Achilles’ Heel slottability are both things many blasters lack. I use this when I really want to max out S/T DPS. Works wonders with Beam Rifle. It’s more than “OK” - it can put a serious dent in your AV/pylon/etc kill time.
Cryo Freeze Ray is a hold with a longish recharge. Holds with longish recharge are exceptional S/T damage when slotted appropriately for procs with maximized proc rates - we all know this, nuff said. I use it to shore up my Assault Rifle’s weakass S/T damage.
Body Armor is fine as auto. It fills out a special niche that way.
LRM Rocket requires two things to be effective: (1) extra damage. For that activation time, you want a nuke. Easy. Slot it with procs and it will be basically nuke-level damage. (2) time to hit a mob before everything is dead. The key is NOT to be dumb enough to use this on the mob your team is fighting. Use it on the next one or something. A 2nd nuke is not a bad thing to have if you know how to use it. The amount of buffs the OP suggests for it is ludicrous. One of those things, sure, but certainly not two or more.