@ShadowMoonlight - l tend to wear Fantasie for day in, day out wear for work. That said I’m often in opaque tights at the moment (weather!) but l’ll be pleased to be out of them.
Remember that sussy belts have a job to do. Some are almost like string that wouldn’t hold up a paper coaster.
Try looking somewhere like Selfridges, John Lewis or Figleaves. As well as Fantasie l also tend to opt for Pour Moi (but watch Pour Moi sizing!) or Freya. Rigby and Peller are good if you can afford it too. I also gave a John Lewis own brand belt but when l last tried to get a second one, it had been discontinued.
In spite of the hand wash only label, all mine go in the machine at 40 degrees on a gentle wash.
Avoid anything you can step in to, it is not going to stop put. Likewise avoid single hook and eye fastening at the back, if they are too thin at the back they cut in and can twist. A comfy belt will sit on your back in the same way as your bra. Ideally look for 3 or 4 hook and eye fastenings so it sits flat and will not ride down. Oh and avoid plastic clasps. They tend to ping at the wrong moment. A metal clasp and a broad back fastening will keep everything in position and in place.
And there is less of a “gravity” problem than with tights!
Remember, they go under your knix!