The thing that kinda sucks about HQ runs, chances are, if your country is being pummeled by both sides, your underwater for player numbers, and then someone bombs your HQ because you cannot mount a decent defence...it really is demoralizing to play without radar - I often just log frustrated into the turkey shooting that then ensues - being blind and outgunned and outnumbered.
Now, if we were to take this idea, that the more fields you add, the easier it is to attack an opponent's HQ (who is winning the war), I would offer perhaps that a spawn point opens up near their HQ for tanks if they hit a threshold to put a damper on their war machine. Perk points be damned, I'd up a Tiger II and just have at the enemy HQ.