This is something I've always wondered why it didnt exist in the original game.  I know the current buff/debuff set for focefields is full of knock and repels so it wouldnt be a simple port of a power set but I think in terms of art assets its a fairly simple set.   
  
Mechanically I was thinking of something like this 
  
1 Deflection Field - Toggle: Self +DEF(Smash, Lethal), Res(Toxic, Defense Debuff) 
2 Personal Forcefield - Toggle Self +DEF(All), Res(All) 
4 Insulation  Field - Toggle: Self +DEF(Fire, Cold, Energy, Negative), Res(End Drain Defense Debuff) 
10 Anchoring Field - Toggle: Self +Resistance (Hold, Sleep, Knockback, Disorient) +DEF (Smash, Lethal, Fire, Cold, Energy, Negative)  The defenses buff here would be minor similar to the passives available in SR or Invuln. 
16 Detention Field - Ranged, Foe Capture (Special) 
20 Dampening Field - Auto: Self +Res(Smash, Lethal, Energy, Endurance Drain) 
28 Temporary Barrier - Self +Absorb 
35 Dispersion Field - Toggle: PBAoE, Team(but not self) +DEF(All) This one reworked to function like grant cover from Shield Defense 
38 Regenerative Barrier - Toggle Self: Invulnerable +Regeneration +Recovery Basically the same as hibernate from Ice Armor