I've tried many sites, even running my own LLMs, but the thing I enjoyed the most, was using OpenRouter combined with SillyTavern. You have to pay of course, although it's not a monthly subscription. You just add a set ammount of money and you just spend it as you generate stuff. There are also models out there that just beat ChatGPT when it comes to RP. In fact, it's quite outdated in today's standards, both in context size/memory, and quality of responses. The ones I liked the most were Claude models. Claude Opus/Sonnet are MASTERPIECE level replies, although they're expensive and requiring a bit of tuning. Claude Haiku is an amazing budget option, specially with the quality of replies it gives and with the self-moderated model you can pretty much get NSFW no problem.