New bird, need advice

Hey everyone ! This is Roy, I adopted him and his three friends today. After setting up their quarantine cage in my living room I noticed his little feet! Info: it’s only the quarantine cage and there are more, natural perches in it. I got them with their cage and already took put things that are not safe for them. I let the perch inside cause I did not want to remove everything they know. I got a visit at an avian vet scheduled for next week to check them all out. I already do have a flock of 6 budgies, two of them are unable to fly. One due to hormonal issues, one due to French moult. I suspect Roy to have French moult as well as he doesn’t really have a tail. My question is: how can I make sitting comfortable for him? Should I add wooden plates to sit on for him? Should I use fabrics to cover the perches ? Especially if he does have french moult it will be hard for him to come around climbing. Any ideas ? For now, he is able to fly, but not very good 😅

Thank you in advance !