In reply to Dave the Rave:
I was born and bred in Colwyn / Rhos, and after 20 years away have finally come back and have no intention of ever leaving. There's not much if you want nightclubs, but plenty of good pubs/restaurants etc.
Access to Snowdonia, Anglesey and the coast is fantastic - especially good if you have sea kayaking / mtb / cycling interests too for weather alternatives. And even ignoring mountains and climbing, just having the access to the Ormes, Nant y gamar, Bryn Euryn, etc and all the beaches for morning / evening walks is worth considering.
Personally I would stay out of Llandudno itself just because of the traffic issues when the holidaymakers are in town (don't mention the Extravaganza.....) but usually it's fine.
Beacon + Indy are closer indoor walls than queensferry (and there are allegedly indoor walls at Llandudno junction and Llanrwst leisure centres, but I don't know anyone that's ever used them).