I'm using a Skarmory for a wall... Mine has high 252 defense and speed EV's, but I was thinking that maybe I should start over and add some Sp. Defense EV's, right?
It all depends on what you want. Physically defensive or Specially defensive.
Physical: 252 HP / 232 Def / 24 Spd
Special: 252 HP / 232 SDef / 24 Spd
Credit to Smogon.