I mostly GV and I use the M-8 ALLOT. I die more than I live, but the perks just keep pouring in whether I kill a Panzer H, shoot down a radar, get some autoguns, or just simply pick on poor Scotty.
I have enough perks to Use Tiger II's every night for at least a month, but there is no challenge to using an awesome tank like that. Killing Tiger I's, Panther G's, T-34/85's is a challenge with the M-8. I often die trying to get one because one shot and I'm in the tower. But when I do get one.....high fives all around.
ENY is never a factor if you use a non perked ride, stick with that ride and learn it. Same for planes. Get good in a mid war plane and you can take on just about anyone under the right conditions (alt advantage attacking from the sun) and crank out the perk points so you can take out those expensive rides when ya feel like it. Read Boelcke's Dicta. You can also get some of those achievements. The C-2 is a fun plane. Leather seats too.
Sometimes the T-34/85 is not available because my country has way way more players than the others, so I go right to the M-8. Killing two Wirbs or two planes on the runway is an easy 10 perk pts regardless of the ENY at the time.
Once in awhile in the evening I do not see any GV fights........so I start de ackin'g a v base.........they come out looking for that M-8 and before long there are lots of gv's from both sides having a fun battle.
ENY never stops me from having fun.