there are many beaches that hydrofoilers use in the north of the island, flag is the most popular, but your right in that it is risky for your gear if you are not that experienced, and the shore break that happens regularly there is maybe the biggest problem in the onshore winds for many less experienced or even experienced foilers that are not used to being pushed back, and it gets worryingly busy so no room to fall in
with so many ttips on the water in a very limited space so plenty of this
And this location is the norths easiest place to foil from! its a foilers dream location, with often massive wave sets from the close by reef breaks, the massive expanse of sailing area, lots of super friendly foilers from all over the globe, great sandy beach, and on light wind days you can be the only one out on a decent foil kite and big wing, great to see the crowd of Ttips standing watching from the shore wanting to get out but simply cant do that in the very common light wind times of early morning or late afternoon.
The many other northern beaches are not worth mentioning as they can be very scary unless your a very good hydro foiler, but when your up to it then they are waiting and normally much quieter.
the only super safe but still great location is Matas Bay, half way down the island, flat water,deep safe launch, no shore break, no waves, safe for you and your gear, beach is rustic, good car parking a few yards from the beach hire center and shop, superb rescue service with many jet skis on duty to pull you back to shore,wind is cross off most days,rescue needs to be paid for before you go out, 50 euro for up to 3 rescues but unlimited time, no expiry date, I paid my fee 3 years ago and its still valid as no rescues, loos and shower included in the fee. sotavento is just far too gusty, and not that enjoyable overall, keep trying it as it looks superb, but hate the place every time I do,
rescue fee is a must do at flag as the wind often just switches off completely with no chance of keeping any kite in the air, risk is high of a swim in.