In reply to Chris Sansum:
Hi Chris
I love long rock routes ... probably because I struggle when it gets hard.
There are a lot of great long routes in Costa Blanca and Valencia area that are usually good in December. I do my main foreign climbing trip in winter to escape the UK winter and have tried most of the easily reachable (cheap) places. The further East in Mediterranean tends to have less reliable weather in December / January (e.g. S. France, Sicily, Sardinia, Greece, Turkey) - but anywhere can have bad weather in December - last year there was snow in Costa Blanca in January.
Costa Blanca and Morocco are my favourite destinations
Leyva (my favourite ... but only about 200m) - there are 100 or so long routes here in the local guide available in El Berro that are fully equipped / partly equipped or completely trad. Nice strong lines and rarely busy. Loads of great routes in your grade range. (the ones in the rockfax guide are all excellent ... but there are loads of other equally good climbs)
Cabezon d'oro also has loads of routes that are fully equipped / partly equipped and there is a newish dedicated guide available at the climbing shop in Alicante
Montanejos
Montanejos is also great but tends to be a little colder but fine if you pick a route in the sun... once again there is choice of fully and partially equipped routes. There is a warm spring in the river thats a real treat.
Morocco - Tafroute area is fantastic for trad and is warmer
have a great trip