We've been to :
Faliraki (Rhodes) Beach isn't anything special but it's economical. The
Weather during the summer is always perfect if you don't mind the heat. For the most part the people are nice. OTOH last time there was one idiot (A local I think) who set himself up on the edge of the textile zone pleasuring himself. Shocked/scared the textile walkers. At the other end in the bushes there can be a different type of activity so best not to walk down there if you're easily shocked.
Outside of that the people running the place seem to be putting in more and more umbrellas which wouldn't be bad if the equipment was at least comfortable. OTOH the prices tend to be low.
In France La Seyne-sur-Mer. Beach isn't the easiest to get to. You'll have an easy hike from your parking spot . But it's a good 15 plus minutes from the nearest parking spot walking in the forest/park until you reach the beach. Beach is rocky and very natural. Most of the people on any given day are locals. Some Germans. Some Italians. It's too much effort for the peepers but you will have the occasional runner accidentally end up there. Town feels a little run down. It's not luxury south of France.
In Barcelona if you aren't shy two of the beaches. One is legal the other accepted by the
Police. Easy to get to from the tourist hotels but not for the shy.
Further south Parque Regional de Calblanque outside of Cartagena I love. But the most modern thing you'll find is the parking lot. Everything you'll need or want will need to be brought with you. Plus they have a limit on the number of cars which means after 10 am you may have to wait for somebody else to leave before you are allowed in. Virtually 100% Spanish. Very private.
Vera Playa is easier to get to. But the beaches aren't on the same level. You've got a number of textile voyeurs. But if you aren't shy and want something organized it works.
Even further south Playa de los Muertos. Which we thought was officially a 100% nude beach. By 11 it had turned from nude to almost 100% clothed. Beach is nice . No services but gorgeous. But busy. If it was less busy it would be great.
We tend to not worry about services on the beaches. Most of the above you'll want to pack everything you might want for the day.