Solution exist, though : let us post films in forums showing those lamers bailing and bailing again (5 times same guy in a row yesterday, thats becoming a way of life for some...Isnt it, ******4* ?) 
THAT I like. Peer pressure does have some effect, I've tried (and to a small extent succeeded) in discouraging teammates from bombing 'n' bailing. I don't know anyone who respects folk who bomb and bail, and if players would grief those who regularly engage in it, it might become less common.
I disagree with the hardening-the-HQ idea because it would result in HQ almost never getting killed (how often do multiple sets of buffs hit strats nowadays?). And limiting the effect of a downed HQ would make the risk/reward ratio in hitting HQ undesirable.
If hardening HQ to some degree ever happens, I hope HT also makes HQ stay damaged a lot longer than it currently does, so that a subsequent strat run has the chance to finish the job if the 1st attack falls short. A damaged-but-not-downed HQ heals in what, 15 minutes now? Link HQ damage repair time to city strat damage, or have HQ damage last an hour (instead of 15 minutes, or whatever it is).
But I like the system the way it is right now. It takes a long flight and precision bombing to take down HQ, and the value of downing the target should be commensurate with the amount of time and effort involved to do it.