if you want to fix engi/magus its a bit convoluted because of its turret mechanic and the ability to one shot turrets, its why in keeps where you can hide them and they get buff engi is a threat, in open they are less so. Any class with a "chunky" mechanic becomes problematic ... finding the middle ground is easier said than done. Making them able to be aoe healed and take less aoe dmg might lead to other problems, this class is so overly tied to its pet unlike WL / MSH ... just naturally making their pets have more base HP might be fair? In premade fights if enemy uses a WL with a pet the pet just gets focus and killed, you wouldnt bring a engi to premade and its mechanic can be shut down so easy nullifying it.
I understand this class needs love i am for this... but time and place, when order cry so much about losing cities, you give slight buff to one of the culprits why they lose pug cities, because stacking engi's does not work in open field (only excels in forts/keeps) and when things are already stalemated for EU prime, this is a buff for defensive siege mentality... when we should be looking back a couple of years ago when the campaign switched to making Battlefield objectives great again, and fights over BO's... somewhere along the road we lost sight of this and it became get to rank 2 siege keep, siege wars are the weakest aspect of ORVR, they are a part of it sure but its not the strongest unique selling point of the game... the big open field battles are epic, not the same usual suspects rushing into oil at a keep.
Current problems for EU Primetime to help reduce burnout