Make Up My Mind: Marriott Hotel + Air - STX or GCM
 

Tough choices! Planning spring break (self, wife + 10 year old) for late April17. We like the beach, some snorkeling, eating, seeing the sites. 50% beach time, 50% everything else.

We've narrowed it down to using a Marriott Hotel+Air so we can get the SWA Companion Pass again for 2 years; we've done this before. It's either the Renaissance Carambola or GC Marriott Beach Resort on SMB. We've been to the Carambola before, not with our kid in tow however. Here's the coin toss we need to make:

St Croix Renaissance Carambola
+ Hotel + Air Cert: 230k pts (Cat 6, maybe 7 I forget)
+ Easy to fly in via Southwest into PR with comp pass, then a puddle jump. 60k points + $~350.
+ or - Been there before; know it but havent done it all...
+ Easy to navigate, with a GPS and I love a Jeep trip
- Snorkeling is great, but not so sure it is for a 10 year old beginner.

GC Marriott Beach Resort
- 290 points (would still get Rapid Rewards, we'll use the Comp Pass a ton)
+ Resort is on SMB
+ Turtle and sting ray adventures
+ walk out shallow snorkeling, key for my kid just learning to snorkel
- The dates we are traveling both Delta and AA are BIG points. Total air will use up 300k points in coach.

I treat points like cash, not at the risk of not enjoying their use, but the air points to GC spook me. Its a lot. Southwest is 60k for 3 of us r/t + $350 in r/t puddle jumps on Seabourne.

Any strong feelings out there on either island? In tow with a 10 year old? St. Croix would be easier for us, which is also my hesitation. My 4th time in Aruba is when I realized easy isn't always the most fun. I'm reading mixed reviews on Grand Cayman: outside SMB not much to look at above the water, but the turtles and sting ray adventures sound like big memories for my kid.
I'm torn. Help me flip the coin? :D