Yes, she is. We were lucky to have her around. Destroying the Flagship single handed, rescuing the Cordi Queen single handed, forging the first Terran-Cyrvan force ever, made up of new recruits mostly into an elite fighting force and leading them to a string of victories, with inferior equipment to the enemy, all at the tender age of 65...
As much as I like Crystal, you give her a bit too much credit here.
"Forging the first Terran-Cyrvan force ever"? She didn't found the JGASF, she joined it. Sure, after a certain stage of training she was chosen as the leader, but she still originally joined up as just another volunteer among equals.
"Destroying the Flagship single handed
"? And what about the whole fleet that enabled her to get close and especially Infi's sacrifice?
I agree that she's a hero for what she did and a good strategist for coming up with the plan, but to say she single handedly destroyed the Flagship all on her own is definately not true.