Hi Sanstef Holfan - - - The first week in May when the season opens, you will find that not every establishment will be open.
This can be good as it concentrates the people into those open and there should still be many visitors there.
Yes it will be a touch quiet, but we (and many others ) have done May and liked it.
I doubt there will be any water sports open until later in May - slight possibility of odd showers, but should be great still.
Enough to keep you busy!! May feels fresh and if the sun shines every day - you will enjoy it!
Zoe is another who goes every May, so she may well comment, likewise a few live there and have views as well!
Have a great break!!