Two of my sparring partners are 6'6" and 6'7" respectively. I am 5'10" 250lbs.
All that reach can be a complete disadvantage if you know how to get inside on someone. If the tall guy is good with elbows and knees then he can hassle you a bit, but if you can slip a punch and get inside the reach and throw punches with your legs you can destroy a taller opponent.
Last time we sparred my 6'7" friend tried to throw a quick left jab followed by a quick spinning back fist. Most people back up to aviod the jab and get caught by his backfist HARD, well I slipped the jab and I saw his hips start to turn for the backfist and stepped inside and caught him in the face as he came around. Broke his nose.
It's all about working with what you've got.
I personally don't think that Sylvia is talented enough or in good enough physical condition to be champ of anything.
The UFC HW division seems weak to me. I wish they'd bring in some new people.