If you look through the previous advice from Jim on the Forum, you'll see he has a nice formula for how much of your rack space should be roughly devoted to different types of modules. I found that quite useful as I, like you didn't have a clue what most of these modules could be used for. I understood what an oscillator was, what a filter was and others things like lfos and envelopes. Pretty much what you play with on a soft synth.
Over time I realised I loved sequencers and also learnt that vca's, attenuverters, dividers, multiples, cv mixers etc were really damn useful. There is a use for absolutely everything.
I'd keep the Turing machine and like Jim and Lugia said there are so many other uses for it.
I'd encourage you also to watch this and particularly the last bit of this video ( I watch all of it about once a week and always learn something new) about logic modules and the Turing machine from mylarmelodies you'll want to keep it, I guarantee it :)
Happy patching :)