The Devils Knuckles and Sehlabathede are definitely worth the visit. Its classic, just don't exepct the dramatic escarpment cliffs of the Northern Berg. Lovely area for caves, tarns, sandstone formations, easy passes, and the Knuckles themselves are excellent for scrambling.
Masubasuba is worth a visit, agreed. Scramble up at least one of the Hodgesons peaks. Can be combined with some of the other passes further south too.
If you want something harder and very remote, consider Vergelegen. You may want to focus your first visit there on Thabana Ntlenyana and nearby passes, but it has a lot more to offer than that.