The max speed should definatly be maxed to like x3 maybe even max x2.
Damaging the EV isn’t too much of a problem if you play competitively I guess because you would have your team balanced to have spam players(think the Arty/Strike mercs) who give ammo aswell as abilities to spam damage the EV. Maybe give some merc(engineer mercs?) some sort of EMP nade that temporarily stals the EV? This might add a nice dynamic where a team has to time there EMP ability engineer with it’s spam based teamplayers to damage it?
ps: just first thing that came to mind
brainfart 1: To make that EMP nade ‘not only about stalling the EV’ make it temporarily disable things like Turrents/Mines such things. This way the merc having the EMP ability will have to consider what to use it on, give his team window to get past a turrent/minefield or use it to stall the EV.