Will try to pack in 2-3days 'casual' sport climbing, ideally with good stuff through the 6s and low/mid 7s.
Also, any advice as to which crags I should check out greatly appreciated.
You're spoilt for choice at that standard. Also the rock is generally a lot better than Pennine lime.
A few things to consider / rule out: Marine Drive is school-holiday-banned until 6pm (alas including Axel Attack Wall), The Diamond is quite complex and might still have bird-bans, LPT is obviously quite tidal (and can bake in the morning sun), and of tangential interest Tramstation Crag and St Tudno's Upper should avoided like the plague there because the sport there was created in a cuntish action of retrobolting good, protectable trad and doesn't deserve any ascents.
Otherwise: Hornby Crags has a nice selection scattered along in a fine (but not small children / nervous dog suitable) location, and gets the shade until early PM or a glorious sunset if cool enough. Particularly popular at Sticky Mix Wall.
Penmaen Head has a good selection of 6s on quarried rock with some nice flowstone and ergonomic holds. Can be very popular, again early shade or afternoon sun.
Llanddulas Cave is great if it's hot, very shade and gets any Northerly breeze, plus cool routes on cool rock (and a cave to hide in).
Dyserth has some interesting crags to check out.
Penmaenbach Quarry is good for different climbing on quarried, errr, microgranite? Or basalt or something similar?
Obviously if you get the tides right for LPT or evening sessions at Marine Drive then they are ace.