I'd have to go for Roy. I know there's a lot of love for Max, but in reality it's Experience vs Youth.
Roy was the best UN Spacy pilot up until his death in 'Pineapple Salad'. Max would be the best pilot in M7 and if he's still alive (and as young looking) into his 60s, he'd still own pilots like Ozma.
The best male Zentradi pilot was Quamzin, and the best Meltlandi pilot was Milia, until marrying Mr Jenius toned her down a little.