On rare occasions I like the Stillwell Audio Transient Monster as it's incredibly simple to use, incredibly affordable, and can work nicely in some cases to bring back some punch and snap to tracks that were over compressed. It's similar to SPL Transient Designer but better bang for buck imho. Definitely not a "go to" tool by any means but nice to have in the tool box and a lot easier to dial in than a lot of other upper expanders.
Transient Monster | Stillwell Audio - It's About The Sound
Best regards,
Steve Berson