Well that's different than "Are Player Defenses too high".
A small adjustment or two likely might help.
I prefer ideas adding an effect to the existing powers, at the appropriate levels, recycling existing in game mechanics, while being mindful of power creep.
Tweak Examples:
Deflection Shield - How much Toxic damage do teams encounter at higher levels? Maybe adding Psi makes them more relevant late game.
Force Bubble - A slow effect or something for targets able to penetrate might help. Or simply some -def or -res.
Power Creep examples:
The dream for Force Fields would be damage from knockback distance
Incarnates adding damage to Force Bubble or Repulsion Field
Detention field being able to slot Hold procs
Lastly, let's acknowledge, many of Force Fields powers are simply contrary to current popular in game tactics.