Yamagen, because Japanese is usually done well in Japanese tourist detinations.
Yamagen is not what it used to be, more fusion these days, like the slightly better known one in Mermaid Beach called Etsu (white barn door). If you want good Japanese at a high price, I believe The Star has a good restaurant, but in Surfers, there's a lovely Japanese restaurant called
You.
I like to dine at a dumpling/Chinese restaurant called
Peter's Awesome Dumplings & Fried Rice that's in a mall on Cavill, when I want that sort of cuisine. Never had an issue, touch wood.
The small chain of Chiang Mai Thai restaurants offer great Thai food (Thai owned).
I would have previously recommended the Northcliffe Surf Club (still nice), but their COVID menu offering really doesn't do it for me compared to their previous menu.
Baritalia, near the tram stop at Cavill, is really good, and I've eaten there as part of a work function before.
You tend to have nice dining options on both Chevron Island, a short walk from SP, and in the Via Roma complex on the Isle of Capri – depending on where you're staying, can still be a short journey. In fact, Chevron has a nice restaurant called Fu Manchu and the sister restaurant is on the Isle of Capri called Madam Fu – one of the staff working here is a Qantas FA.
A little further afield (uber) you have Lupo and Etsu in Mermaid Beach and I recently discovered a Cambodian fusion place called Bunnath Kitchen in Robina.
It really depends what cuisine you're after as to suggestions though. Also perhaps, how much you want to spend. Anything down Cavill is likely to be busy, despite COVID restrictions, as well.