Revelation takes even longer to bring the Doctor into the action than Earthshock, though it's rapid compared with some other season 22 stories. By the time of Revelation Saward was firmly a student of Robert Holmes and was taking away, perhaps, some of the wrong lessons, including the limited number of female roles. Another factor, as you point out, is that the first episode stands alone, telling most of the caves story where the Doctor and companions begin a parallel exploration to the survey team rather later in the episode, after the character exposition scene in the TARDIS.

Emotional Cybermen have been around since The Moonbase; there's almost always been a suggestion that their proclaimed lack of emotions is self-delusion, or at least a failure to recognise their own emotional capacity.

I think Beryl Reid's casting worked on paper - it's co-opting her butch-leaning lesbian persona from The Killing of Sister George, apparently, which I haven't actually seen - and does on screen even though one can imagine more effective readings of her lines.