Weather is always a variable - we always go to HH the first week of Nov. Three years ago it was very chilly. We only got in the ocean once (the kids just had to), but the heated pools we wonderful. In 2000, the weather was fabulous - mid 80's every day. So it's hard to tell. Even with the chilly weather, there was plenty to do and it was a great week.
I've not been to Vero, but complared to HH, my parents did not care for it as much. Of course, that's their opinion - you may love it!