OP the Northern Monkey side of Winterfold has quite a few trails you can take in, ride back to top via tracks or road at far end where Fly Tipper (now flattened) used to be. Tons on Pitch (try and lookup trails like Supernova, John Baptist, the variois T trails (T1, T2 etc). Worth noting that if its wet then Winterfold and Putch aren’t the best places to ride. Holmbury is always drier.
Will send you a 4hr XC plus type ride which starts at Newlands Corner and takes in a mix of natural xc and a few better known built trails. Its not a trail centre style ride but a mix of what the SH has to offer, fast natural descents, some views, quite a dry route too.