Hi all!
I'm about to start a new build, and I've decided to try an Explosives + Melee heavy-handed character (on Very Hard in hardcoe mode) in contrast to my highly effective but slightly boring Unarmed + Guns high-crit builds.

I'm planning on using Annabelle (unique Missile Launcher) at long range and Thump-Thump (unique Grenade Rifle) from medium range, but I'm having trouble picking perks because I'm not sure how some of them affect explosives and one-shot weapons. So here are my questions, Fallout gurus:

• Does the Center of Mass perk apply a damage multiplier to the torso itself, or does it add a 1.15x damage multiplier to any PROJECTILE aimed at the torso? For people using Guns, this would make a difference because a VATS torso shotgun blast with this perk could do extra damage to the head, arms, and legs if the player is standing back far enough. For a missile launcher, especially Annabelle, especially loaded with high explosive missiles, applying 15% extra damage to the entire blast because the VATS shot just happened to be aimed at the torso would mean the Center of Mass perk is extremely helpful. Does anybody know how Center of Mass actually works?
  
• Is there an advantage to taking Hobbler over Sniper if the player is exclusively using explosives? Aiming an explosive at the ground seems to be a more prudent strategy if the missile or 40mm grenade has a chance of going slightly off course.
  
• Does the commando perk apply to the Missile Launcher and Grenade Rifle? (Some people would ask why I care so much about VATS and explosives, but it's because Annabelle only does direct damage when using VATS.)
  
• Which makes a bigger difference in the ACTUAL firing rate for the one-shot explosives like the missile launcher or grenade rifle: Fast Shot, or Rapid Reload? I may end up taking both, but I'm really just trying to understand what the firing rate increase from Fast Shot does for one-shot weapons.
  
• Does the Meltdown perk affect Plasma Grenades?

I realize that I can possibly figure these things out on my own, but my current character is at level 35 and I would have to start over and play my way back up to level 14 before I could find out.
Hopefully one of the GECK-savvy PC users will chime in. Now that explosives have gotten a damage boost, I think more people will want to know the answers to these questions.
Thanks!

Also, does Adamantium Skeleton perk suddenly becomes a reasonable choice when using explosives + Splash Damage? Or does the DT increase from Hit the Deck make this unnecessary?

Some answers for you...

1. Center of Mass targets the player who has the perk, ANY weapon you fire at a torso while in VATS has it's damage multiplied by 1.15
2. I assume that's a Dead Money perk? Someone with that DLC will have to take a shot at that one for you...
3. NO to the Missle Launcher, YES to the Grenade Rifle
4. Fast Shot has no effect on Explosives weapons, Rapid Reload affects everything that has a reloading animation
5. Plasma Grenades are Explosives not Energy Weapons, so no
6. The description for Hit the Deck is misleading as it multiplies your DT by 1.5 just for holding an Explosives weapon in your hands, not making your 50% more resistant to Explosives at any time as the description seems to indicate. As for Adamantium Skeleton it would certainly help to keep your limbs better intact when using Explosives at close range.

Hope these answers have helped you out, enjoy your Explosives run as they are much more fun now since the latest patch.

On #6 - Hit the Deck does nothing. With or without holding an explosive weapon. Easy to verify. Admantun Skeleton is still soo-soo. If you are using a Perk every level mod then take it. Other wise pass.

Sniper Vs Hobbler is a good question. I know using a missile launcher, shooting and missing at the head may cause the missile to sail pass and hit no one. That really pisses you off in to spend your AP on a miss. So I would go with Hobbler, at least if you miss it should explode some what close. Never thought of that one.

And like the above poster - Rapid Reload and High Agility are your friends!

Edit: Also the Grenade Launcher/Rifle is horriblly inaccurate in VATS. So I would pass on Commando. Just get a feel for the Free Fire and you will killing stuff in no time. And I would recommend squeezing in Toughness 1 & 2 if you can.

Thanks for your feedback!
I was already going to max my Agility and get Rapid Reload, but I thought I could push it even further with Fast Shot. I'm glad I didn't waste the trait!
It's a bit disappointing that HIt the Deck! doesn't work at all... but maybe this will prevent me from getting too sloppy with my explosive projectiles.
I'm playing on the XBox so I can't use any perk-per-level mods, but even with perks every other level I might still take Adamantium Skeleton if Toughness 1 & 2, the DT implant and my light armor aren't enough to protect me from my own Splash Damage.
I generally use half my perks on enhancing my criticals and supporting my Guns habit (Hand Loader, Cowboy, etc.), but I can ignore these in my Melee/Explosives build so I have plenty of perk slots to spare. Especially with the level cap about to hit 40...

That's bloody brilliant! It makes me want to do explosives and hobbler now. Leave a ton of legless corpses around the Mojave. Would likely get a ton of progress on Limberjack too.