Hope you enjoy it. I've seen them all but am planning to do a big watch/listen from the start once the DVD's have all been released.
I actually like the caveman bits of the first story - yes nothing much happens but it's a great character piece - for the Doctor and Ian anyway, Barbara doesn't really come into her own until the next few stories. It also has a much better script and acting from the guest cast than The Daleks.
I'm not a fan of the Daleks but their first story is very strong - Nation is great at ideas and pretty solid on the action stuff but struggles with dialogue and the Thals are pretty nothing characters - though Philip Bond does some good stuff with his more cynical Thal and he and Jackie Hill do a nice job with the potential romance given that there's not really much there in the script.
Your retcon is pretty much fan consensus - that travelling with humans changes the Doctor and the next story is a major factor in that development though Barbara is just if not more important in that than Ian or Susan. There's also an element that the Doctor and companions had to be more pro-active eventually as there is a limit to the stories you can tell when all they want to do is get back to the Tardis.