Tricky. Ainley and T Baker worked well enough together in 'Logopolis' but I think of him more as Davison's nemesis for obvious reasons. (ie more stories together!) Not a great story, but the scenes between them in The King's Demons after the Master has stopped with the *outrageous* French/Welsh accent and rubbish disguise are superb. Disdain, caution, admiration, disgust...all subtely conveyed. However, I agree with people who rate 'Survival' as Ainley's best overall performance.
Ummmm....Davison and McCoy, then. In that order.