Now then Keith la!
Aye, tis a funny little fucker this, not overly hard, just quite tenuous and can feel a little committing. Excuse me if I go over what you already know or miss out a few moves but here's my knowledge:
At the top of the the crack there's a tenuous move to get stood up on your left foot high in the crack, then followed by a committing move up to the obvious undercut ear hold with your left hand. This is just one of those moves you've just got to go for and it all kinda makes sense, toes smearing on nice little edges. A last hard pull off the undercut leads to better holds. Once you have done this things ease moving right into the rightward diagonal flake/crack with the plant in it and some welcome gear, up the crack to join Firefly, albeit at the belay. At this grade you definitely don't go straight up the headwall but you're right, it would make for an even better route.
Get yourself on Foolish Goolish if you ain't already, great route at a similar grade.
Good luck
Jon R