Originally Posted by Flyby1206

XLR would work for SJU-MAD. You could even use mostly A220 or regular 320s to hit a ton of spots from SJU:

A map from Great Circle Mapper - Great Circle Mapper

The problem is that FLL would also work for most of these and has much better O&D

A map from Great Circle Mapper - Great Circle Mapper

They have publicly said the desire is to make FLL into a connect hub in the future, which would mean a lot of stuff like this.