Hey just reading through your metagross review
http://www.smogon.com/forums/showthread.php?t=80787 and a couple things i noticed that may be worth putting in;
Gyarados and Heatran make excellent team mates.
They cover both metagross' weaknesses with immunities.
Zapdos is a formidable counter to metagross - however any zapdos can be OHKOed (after SR damage) by a Fire Blast (flash fire boosted) from scarftran.
Gyarados pretty comfortably walls metagross using ice punch over tpunch.
Um that's all i can think of off the top of my head but just a couple things i have noticed (i am a fanatical metagross player :D). No offense intended of course.