Honestly you could probably heal ok for heroics and flashpoints up to 30ish unspecced. If your sure you want to go hybrid though it will be a bit slower leveling experience but powers OT will be your main attack. If you don't mind the splash damage ( no cc targets) then explosive dart is nice DPS for the heat cost. Unload and rail shot when available and use missile blast to set up rails OT on a standard or for an on the move ability the cost though is a bit high to weave it into a rotation.
My typical fight against a strong looks like this: open with explosive dart, powershot , unload , rapid fire to cut heat, powershot and rapid fire until unload is off cooldown or railshot procs. Replace powershot with tracer missiles if you go arsenal plus that will proc railshot.
Sorry for the poor grammar,typos. I'm on an iPhone