+Hp/-Atk Ryoma

Personally, I'm not that bothered by a -Atk Ryoma, I mean his attack stat is pretty high. he's still usable but not as efficient. You should put Attack + 3 or Fury 3 for his A skill and probably Vantage or desperation for his B Skill. I'm currently using a -Atk +Speed Ryoma.

It's actually not the end of the world that he's like that, especially if you're f2p. It only causes his attack to be 3 points lower meaning as long as you put him on a team with someone with Hone Attack you'll at least get slightly over the effect of neutral attack Ryoma. I'd recommend Fury for his A slot because he'll have a little more hp to spare and that'll also repair the issue that comes with -atk. None of his skills are worth offing him for so you may as well invest in him. Obviously if there's a focus with Ryoma it wouldn't hurt to try to pull another for the sake of merging if you can get a better one.

Pet him every day to make sure he knows he is loved and appreciated.