Wylie is pretty shagged. I wouldn’t bother.
Risca bike park is running very nicely at present, with the bonus of being able to do a bit of Cwmcarn as well if you fancy. Mynyddislwyn is..er…like it always is, a series of moto ruts people ride down, nice and dry at present. Steep bits super loose. Coed Mawr is all a bit overgrown. Machen a bit of a mixed bag, but there’s a clear run to the bottom. Hafodyrynys I don’t know, haven’t ridden recently.
Of the above, I’d hit up Risca. It’s really easy to navigate because most of it spurs off of the scenic drive and they’re great trails. Not sure if the quarry is on trailforks, but you can see it from the top easily enough and that’s worth a ride. Conda is mint at the moment, Deaf aand Dumb is running lovely and Wacko Jacko is always a laugh.