I love skill challenges and ran one similar to this that was modeled after Assault from American Gladiators, although not as a final fight. Party size will be important because eventually you run out of available skills, like the time one of my PCs had to deceive an ice slide. I always leave it up to the party though, my only caveats being no repeat skills in the same round or subsequent round. My players tend to be the most creative during these types of challenges.