Been there done that
I spent four days at the colony and had a great stay. Nice clay courts, but the hard courts are uneven and lack any real atmosphere. They need to tend to this issue. The beach is beautiful, the staff is great. Tennis games organized, but I would say the average age there is 50-60, so if you are looking for a bunch of younger high level players, it might be difficult. I am a solid 4.5 player (age 41) and did find one guy to kick my butt. Otherwise, it was more social tennis than a workout. Restaurant was good as was the bar with happy hour at sunset. Longboat key is a very relaxed place, and The Colony is a great spot to stay. Look for bargain prices on Expedia, as the fixed rate is pretty high for what you get. They run a kids club which is free, and there is a nice pool next to the beach.