Still hoping for some replies from those who have had these experiences...until then, here is what I have found.
Ray feeding is uber early in the morning (not a problem for my crew), only appears to be offered once per day, and seems to get a small turn out (probably because most folks don't want to get up early). I like the idea of this experience, because we missed out on a similar type experience on a cancelled trip to sting ray city in Cayman Islands. The likely low turn out means more one on one time with trainers and rays. I also like that the "pre-park-opening" timing of this experience, which means we can maximize time pursuing other activities throughout the day.
Seaventure seems like a really cool underwater experience with several touchy-feely interactions with a variety of aquatic creatures. Not sure my crew would be up for the touchy-feely with several of the sea creatures I've seen on videos of this experience on YouTube. This looks to be a more popular excursion, and takes place during park hours.
I am leaning heavily toward Ray Feeding at this time. Still welcome any feedback.