This should be my HA build (can't check atm): http://kalence.drupa...!34L54384!EF9B3
Singularity: 197 dmg/s, 985 dmg on detonation vs. 247 dmg/s, 1235 dmg on detonation with power amp 4.
Warp: 492/1108/1477/246 dmg vs. 617/1389/1852/309 dmg with power amp 4.
Shockwave: 696/696/1044/696 dmg vs. 846/846/1269/846 with power amp 4.
I believe the increase in damage can make a difference, it just depends on the enemy/map and your team if this is the most efficient route to go or if another armor mod might not be better.
%50 extra damage on powers with low base damage is still quite small .. even if your warp is going from 492 to 617, that's still a very small increase compared to detonating more biotic explosions faster .. the other damage #s you have listed for warp are irrelevant if the target is already dead from your detonated BE.
Personally, I don't cast Warp or Singularity then run another direction waiting for these powers to do their DoT .. too slow, I engage enemies and attack them until they are dead. Using a Power Amplifier on an HA (or many other adepts) is a waste as there is little gain to DPS.
The only adepts which really benefit from Power Amplifiers are the Phoenix, Drell and Slasher .. the rest benefit far more from other consumables
Edit - I just looked at your build .. suffice to say we have different playstyles when it comes to this character .. I would never sacrifice up to rank 5 in fitness for more shields and shield recharge to add under (or barely over) 100 damage to my Warp or Shockwave with passives 4 and 5. I would also take faster CDs on Singularity and Shockwave to trigger more BE's faster (which are far more powerful than any other attack you will perform with that kit)