For looks, I'd pick Fire Shrimp. For activity level, I'd pick Skunk Cleaners. Maybe it's just me, but the Fire Shrimp I've seen in tanks are not very active during the daylight hours.
I loved my skunk cleaner shrimp. He was very active and got along very well with all my fish. He was usually hanging out on the front part of the reef.
I have 3 peppermint shrimp and 1 skunk cleaner. My peppermint shrimp (Lysmata boggessi) have developed the nice deep red color with black tails. Beautiful.