Whatever you decide, I would strongly recommend you do not take the tarmac way to O Cebreiro. It's not just the hard surface, but I find the close, fast and constant vehicle traffic to be the scariest thing of all. I did this 17 years ago (from Villafranco de Bierzo) so I don't know if the route I took is the one currently called Pradela or not. I don't think it was the Dragonete, though. But regardless, staying off the road and going over the mountains is truly worth the effort. It was my most difficult day on the Camino perhaps, aside from the 1st day over the Napolean, but it was by far one of my most magical and fondly remembered days.
I may be biased though. It was my first truly solo day, as I had temporarily lost my camino family for assorted reasons, and everyone else chose the road route. I chose to ignore my fears of the mountain route's difficulty and of going it alone. After the first lung busting climb, I traversed the beautiful, peaceful chestnut groves where the first gentle snow started falling. It was so quiet and lovely. A bit later, I was briefly courted by a local farmer. He charmed me by introducing me to both the newborn calf in his barn and his mother. He then walked with me a ways, collecting fallen chestnuts I later roasted at the albergue, and he sadly wished me well when I gently turned down his proposal of marriage.
A while later, the snow fall got heavier and I lost the trail, so wandered off along what I assumed to be tractor ruts, hoping I'd just end up somewhere with a roof. Just as I was starting to worry a bit, Jesus of Ave Fenix came careening, driving at breakneck speed up from behind me with my injured hippie friend Indigo hanging out the window screaming get out of the way, he can't stop, he has no brakes, see you there. I crawled out of the (apparently roadside) snow drift relieved to be alive for another day.
Don't be afraid. Walk into the mountains, friend. It's where the magic happens.