If I were travelling that far I wouldn’t look anywhere other than BPW. Especially with a youn lad and with you not being big into jumps. Plenty of blue and red runs at BPW for you both to enjoy.
Other options are really Black Mountain cycle Centre which I’ve not been to (was booked to go last weekend but it got snowed off – so need to rebook). I think it’s more likely to be muddy than BPW but I fancy trying it out.
There is Flyup 417 at cheltenham which is ok – similar idea to BPW but nowhere near as big / nowhere near the same variety of trails.
You can uplift at the Forest of Dean, but again, that’s not a patch on BPW for a full days uplift fun.
Cwmcarn has an uplift but I don’t think there’s enough variety of trails uplifted for – some of the downhills can be quite hard there from what I’ve heard (I’ve only ridden Pedalhounds and hats not too difficult).