Tom Baker was my Doctor, and at the time I adored the programme, so I feel bad saying this, but …
Tom himself I don’t think was ever anything less than awesome. He is still the most convincing representation of an an anarchic, bombastic, brave, compassionate and petulantly childish alien time-travelling genius there’s been.
However, Doctor Who of the time was still 1970s British children’s TV, so he was up against shoddy production values (always), ropey scripts and supporting actors (sometimes), and casual racism (not often, but unfortunately not never). The Talons of Weng-Chiang is a pretty blatant example of the last (and also the first; it creates a fairly convincing depiction of Victorian London, then lets it down with the world’s worst ever giant rat).
That said, there are gems, and more than a few. If you’ve not seen it already, you have to see Genesis of the Daleks. It makes explicit what was previously implicit (the Daleks are basically Space Nazis) without making it cheesy; it introduces the first (and IMO greatest) Davros; and it explores the ethics of utilitarianism vs deontology as they pertain to genocide, which is pretty hardcore stuff for a kids’ tea-time show.
Another must-see is The City of Death, which may have the best script of any Doctor Who serial (courtesy of Douglas Adams), and some of the best supporting actors (Julian Glover as the baddie, and John Cleese in a cameo).
The last two stories, The Keeper of Traken and Logopolis, are very much worth watching, both for pretty strong weirdness (especially the latter) and for introducing Anthony Ainley’s incarnation of the Master, who I think trumps John Simm’s (though not Michelle Gomez’s).
And there are plenty of others. But be aware there’s some dross too.
Anyway, that rat: