Commenting on request...
(1) I'm honestly not sure what you're talking about...Are you asking if having most of your attackers on the special side is a bad idea? I have no idea where you got Mamoswine from as he doesn't seem to fit anywhere on the team, but I guess SD Lucario couldn't hurt. Extremespeed DID get boosted to +2 priority, and in the current metagame SD Lucario certainly is no slouch, especially if you run Ice Punch (most Gliscor don't outspeed these guys anymore). I wouldn't get hung up on the idea of "physical-special balance", because in all seriousness it matters very little, but I could see SD Lucario working out pretty well for you.
2. Yeah, I'm sure. I don't see anything that Metagross really helps you with. Simple Agility sets are really not sweeping anybody, considering how the metagame looks, and without recovery he isn't the tank he was last generation either. You seem attached to him, so if there's a particular niche he serves, let me know, but otherwise I fail to see his usefulness. Heatran is much better in his slot, especially when you consider annoyances like Nattorei or SD Scizor popping up everywhere.
[20:44] <@DrFidget> Am I the only one who still uses the internet strictly for porn and videogames?