Just got back from a stay at Le Toiny. They have some big renovation plans about to start. (new villas, new pool decking setup, beach build out...) there was no construction that we heard during our stay but our villa already had a remodeled bathroom. I agree le toniy might be too quiet for a couple 18yr olds, but it really depends on them..

I would look for a villa rental if there isn't availability at eden roc.

Le Serano was mentioned, I only saw it at night but it looked pretty nice. It's the slow season obviously, but I did find it a little odd that we were the only ones eating at the restaurant there the night we went.