You should not be allowed to roll Need on loot that your class can't wear, period. It blows my mind when players roll Need on stuff that isn't for their class... my mind has been blown even further by the fact that players have been asking Bioware to change the roll priorities on loot since beta and they haven't fixed it yet.
The only thing they have to do is limit Need rolls like this:
Guardian/Juggernaut - roll Need on Heavy Armor with Strength only.
Sentinel/Marauder - roll Need on Medium Armor with Strength only.
Smuggler/Agent - roll Need on Medium Armor with Cunning only.
Consular/Inquisitor - roll Need on Light Armor with Willpower only.
Trooper/Bounty Hunter - roll Need on Heavy Armor with Aim only.
If the armor doesn't match your class Need table, then you can only roll Greed. Then, you're only fighting with dps vs. tanking and dps vs. healing gear rolls. I think that's astronomically better than rolling Need on loot for your companion that you don't see anymore post 50.
Yes, I have suggested this for over a year now. Hopfully Bioware will wake up soon and read the thousands posts made by the community regarding the problem with anarchy lootsystem in The old Republic.