I'd agree, but even if you dont upgrade cage right away, linear tube uvb is important on whatever cage you get. linear means hes getting uvb no matter where he is, not just when basking, and you want to make sure they always have access to uvb no matter what they feel their temp should be. I just got a 24" one that's way to big for my 16x16x30, that way when I upgrade cage, light is already ready for it. the only thing id say is, that basking spot looks really close to the light, have you measured the temp at the basking spot?