Saddle really depends on very intimate details of pelvic geometry rather than weight. Don't spend on a lot of money on one saddle. Instead start with that SMP TRK - it's the closest thing to a universally popular saddle - and then if that doesn't work, try different used touring saddles or the older heavier racing saddles until you find one that works. The Selle Italia Rolls and WTB Rocket are other good choices. And Brooks, of course, have their fans - but expect a break-in time.