I was in Rhyl last week. The west end, where the fairground is, is pretty run down and I think the fairground itself has recently closed. Rhyl is going to have lots of money pumped into it over the coming years, hopefully.
Depends what you like doing though. There are nice places in the area.
Fraid I can't make any more constructive suggesetions but bumping for someone who can.
Will you have a car, for instance?
We used to go to Rhyl quite often a few years ago when my SIL lived in Chester & DS & DD loved the Sun Centre - especially the surfing beach, but I seem to remember a post on here that said it had gone downhill a bit since then.But Ryl is probably worth a visit for the Sea Life place & the general slightly tacky (in an enjoyable way) seaside atmosphere.