In reply to Robin Woodward:
Fall-bay/Mewslade in general is the place to spend at least a day, nice mix of grades and tidal/non-tidal routes.
Osiris is THE route of Gower. Well, actually the direct finish (Lazy Sunday Afternoon) is
THE route of Gower, but it's might be a bit out there for the OP. It's pretty safe though and not so hard, it just needs a bit of confidence. It's certainly easier than the "E1" to the right, Seth, which would be E3 5c if it were 50 miles further to the west.
Juniper Wall is great but only really worth a visit if you can tick the E2s that are to the left of Assassin, neither of which is particularly easy; the majority of the other routes are rather samey. It's a nice bit of rock though, and usually sheltered from the prevailing SW winds.
Paviland is of course worth a visit if only to laugh at the vegetation, before realising that the many of the routes are actually very good - East Gully Groove is a cracking HVS and Shelob is unique.
Three Cliffs for an easy day in the sunshine, though all the routes now are getting very polished. Arch Slab has one unforgettable move but otherwise Scavenger deserves it's praise as one of the best VSs in S.Wales.
Little Star Wall is a gem but is very small and a long way to walk, I'm not sure I'd recommend it for a weekend trip, unless you go with a bucket and spade and make a day of it on the beach.
The multipitch adventure up Great Tor is fine if you like mountaineering, but much of the line is rather artificial (i.e. you can avoid most of the difficult bits) and the 4 pitches feel artificially short.
I agree that Boiler slab is the best venue for non-tidal lower grade stuff, though when the wind is blowing it can be bitterly cold. The VDiff on the left was my very first outdoor route, climbed on a top-rope about 25 years ago