In reply to Duncan Disorderly: I think Paklenica would be a great location for you - there's loads of variety in the climbing there (I know you're after single pitch, but there's good 2 or 3 pitch cragging and mountain routes too) and the area is well set up to cater for families. There are good, cheap facilities and beaches all within easy reach. You can also easily arrange trips out to the islands.
We didn't find any big crags in Istria where there was a concentration of routes, but there was plenty to travel about to and the peninsula is understandably attractive to Italian, Austrian and German tourists because it is a very beautiful area. There would be plenty of stuff for the family, but the climbing is not as easy to arrange.
We flew to Venice, which would be great for Istria, but if you were looking at a visit to Split then there'd be a long drive inthe offing.
From Venice, we travelled to Osp (approx 3 hrs, including getting lost at the border), then drove to Paklenica (1/2 day) and returned via Istria.
It's a beautiful place for a holiday.