Items look good. I would suggest that you go with though. Panth has no escape mechanism, and CC will kill him. The items are nice though.

Runes: Marks should be ArP or armor depending on the role you take in game. If you are wanting to be more tanky, than Armor. If you want to be DPS, than ArP.

Seals should be Crit Dmg or Armor. Again depending on what role you are playing.

Glyphs should be Cooldown reduction. Works well with either roll.

Quintessences I would make ArP or armor. Again depending on your role.

Masteries need to be either 21/9/0 or 9/21/0. If you are wanting to tank, you need all the defesive things. If you want to DPS than you need more power in offense. Good items and some good runes, but you need to clean up the runes. This has potential, you just need to clean it up.

Adding a better description will help too

toooo mannnyy runes...ive got no overview take the runes u think are best for him and the rest u write in discription

say smth how to play him,what u should to
mid lane side lane ,farming agressive maybe skill combo and so on
a bit ´bout the summoner skills and other good possibilities

i liek the thing u didnt max out the offensive tree,its jsut **** 5% more dmg but ur mastery tree isnt that good for panth ^^
1 point just in archmages savvy, no point in alacrity 4 in sorcery 3 in sunder and 2 in
offensive mastery
the defensive mastery is ok with the 60 hp bonus

the most people dont like builds without any discription ( me too) but ill give you an + =)