We took my youngest when she was 8 weeks, the other two were almost 2 and almost 3 at the time. It was a fabulous trip! The baby spent the whole time in the sling, we even only brought a single stoller, and that was all we needed (10 days). It was not hot, so it was great for the baby, I did not have to worry about heat, and since I was wearing her for 10 days straight, it was cool for me as well. Honestly I don't think we took it much slower than we have the other two trips, I fed her where she was hungry, (we nursed, so if she was hungry she ate), she slept almost the whole trip. She slept with me in the bed at the resort, my almost 2 year old slept in the crib, and my other daughter slept in the bed with my husband. I would not hesitate to bring an 8 week old, they are so portable, we actually planned the trip at that age because I did not want to wait until spring until she was 6 months. My kids have all been very early crawlers and sitters, and I knew at 6 months she would need much more stimulation, rather than just being carried all day. My other two at that age were great as well, since I wore the baby most of the time, I would take a kid (and the baby) on a ride, and my husband would have the other one. Most rides I did not even have to take her out of the sling. And, man I caught a good nap in spaceship earth (as did my 2 year old!!).
I felt great too, I was only 8 weeks postpartum, but her delievery and recovery was so EASY, and that made a difference too, so think of how you will feel at 8 weeks.
Good luck, if you have any more questions let me know
Heidi