Advice that won't be taken
My advice to all young'ens: don't start. If you've started, stop. Take the money you save and go have some REAL LIFE experiences, some REAL LIFE relationships. With a real relationship, real emotions, I think all your problems will disappear. And if they don't, it'll be fun working through them with an emotional PARTNER.
P4P is just sex, NOTHING more. BUSINESS. It's an orgasm, nothing more. No emotional investment. As you're dressing, you can think of what groceries you need to buy on your way home. Too often, the inexperienced confuse sex with love. You need a real life foundation to keep you grounded when you're adding additional stories, and that's all P4P is.
Neither real life nor P4P is like porn. Porn, they're paid to be actresses, just like ML/WG's, but porn is pure fantasy. It has no basis in fact. It's for 2D stimulation, not 3D. It skews your expectations. Nothing wrong with it as long as you UNDERSTAND what it is.
Real relationships are work, 2 way streets. You have to be supportive, not financially, but emotionally. You have to take her good and bad, have to be there when you want to and when you don't. P4P is one-way, that's why you're paying. IMO, those who have too little real experience with the former, too much experience with the latter, they bring the P4P attitudes to the real world. Guaranteed to make your real short, few, and far between. On the other hand, bringing a bit of real into P4P gives you a bit of empathy for the provider, enhancing YOUR experience. Simply put, you treat her like an orifice, she'll be an orifice. Treat her like a person, she'll be a person.
Advice that might be taken
As others have said, or will say, stop with the porn. Lower your expectations, enjoy HER experience; it's just sex.
Check out the rosters, here and on Locanto. Get WeChat for rosters. Check out the photos. Yes, I know all about photos, but find someone who you find attractive in some way. NOT perfect, just something that intrigues you (nice rack, cute face, nice shape, nice smile). Rather than SYT's, I'd suggest older, at the lesser shops (heresy I know). But there, you have more of a chance to be seen as an INDIVIDUAL, rather than just another widget on the assembly line to be processed.
Book an hour. Take your time, relax, enjoy. For me, I don't consider the massage time wasted; it's relaxing, and can be quite nice. Or brothel path, enjoy the foreplay. My experience, older equates to more experience, better chance of a PSE experience if that's your thing, or even GFE. She appreciates the business and will work WITH you. See her more than once, so you feel comfortable with her. Be honest; they've heard IT ALL. Have realistic expectations; don't expect miracles, fireworks, angels singing. Like riding a bicycle. You fall a lot at first, but then, just pedal along and enjoy the ride, the scenery. Enjoy the trip; you'll come (pun intended) to the destination.
WADR, your asking for recommendations is part of your problem - choose for yourself, who intrigues YOU. Likewise, don't be concerned about nationalities - KPOP, Korean dramas have nothing to do with selection. An attractive woman is an attractive woman; nationality only pertinent if you're there for language school. There is no "best" nationality; it's all about personal dynamics.
Lastly, to repeat, P4P doesn't teach you anything about REAL LIFE relationships, doesn't prepare you for REAL LIFE. It's just a facade; recognize it as such.