Thomas, very impressive results! Doing a 100 Km race was amazing enough, not to mention your 24 hour marathon! It was interesting to look at your speed vs. distance. Also I noticed the longer the race, the more advantage the Mirage Drive has over paddles.
I think your speeds with the Adventure are excellent for a boat of this size. I do something somewhat similar, logging speeds at 2.4 statute miles, one hour and (occasionally) 2 hours. Although it's mostly for exercise, a little competition brings out the best effort in each of us.
You're representing the Hobie/foot powered contingent very well; I'll look forward to watching your results as you continue to post times!