So is it best simply to focus on the obvious triangle on OS map
To get your bearings I’d park at Starvael (0.5 miles west of tower), take the exit over the piece of wood in the far right corner, and head up to the tower. Takes 5-10 mins depending on fitness.
Once there, take the left immed before tower (by railings) and stand there for a moment. Hold your arms out and make a V shape. That’s the area you want to start with. It stretches about 0.5 miles back to the carpark (left arm) and 1.5 miles to the right (right arm). Loads of singletrack, loopy stuff, swoopy stuff, linky bits, drops, rolls, jumps etc.
The other side of the tower is more expansive and probably easier to miss stuff because it’s more spaced out. Plenty of stuff – you just need to find it.
Enjoy.