Not sure if Engi will be tied into another class, however, as a halfkin engineer myself I really do enjoy the evasion. With a few EVA stats from gear and 1 movement speed ring and cloak, I find click running stopping, attacking, very easy. Currently doing Delphi with ease. I didn't need a PSR but I picked one up just because it made things so trivial.
I chose to put a lot of points into the +STR talent, as well as the Commando heroic trait, with lvl 43 crafted set (white wolf) and random blue weapon I have almost 450+ strength. 10% Movement speed seems adequate, replaced screaming ring with PSR.
You can always get 1 item to give you 5% movement speed (Froggy) but you can't use 1 item to give +30% EVA (to my knowledge, sorry if I am wrong)