Momentum is the theoreticaly better choice because it actually takes some skill to use. Nemesis is worse but requires nothing but a button press every 2 minutes. Nemesis should not and never will be better than Momentum for that reason.
Momentum = good players, min/maxers rewarded with the best possible DPS results
Nemesis = Players that are unwilling or unable to use Momentum and pay a small price in efficiency (~3-4%)
That's actually good design.
You know that you can just simply use Fel Barrage and GT in case you have to walk back to the boss?
Also jumping away to to more damage makes perfect sense: You are basically repositioning yourself, looking for weakpoints in the enemies defense.
While I agree with some of the points you make (e.g. raise Momentum window by 1-2 seconds but decrease its power to make up for that, Eyebeam doing not enough damage...), this is not one of them.
Stormrage US | Aesryn