Yeah Torchwood is very much the 'Doctor Who for adults and not the whole family.'
I agree with starting with 9 if you are just starting out, but that's because there are elements that started way back in the first few seasons that are still playing out today. Like the whole River Song saga. You wouldn't really get the full impact of who she was and all that.
And this latest season has a definite old-Who feel to it. From the opening credits to the writing, it just seems like the more traditional Who rather than the reboot in a lot of ways. I think it's awesome. Capaldi is amazing.