1 drive is not happening. No simplified cheapo way out here, just the usual 2x10/11 set up.
I said simplified, I definitely didn't say cheap!
I'm honestly a bit confused here: who is this bike for? You seem to be building on commission but you don't seem to be considering the person that's gonna have to live with it! For instance, have you asked the rider whether they would have any use for a gear display? Cos' it's looking like you're in a minority of one here! Also, (and probs more important) what is the gear range that they are most likely to ride in? perhaps she(? Ruby is a lady's bike isn't it?) doesn't use the biggest (or smallest) ring, a lot of folks rarely change front rings.
You are right when assuming i am complicating things, but this is what i always have done to challenge myself and to discover new things. Looking at different components weights and other specs allows me to see the bigger picture and how things correlate. Personally, this is how i progress!
Please don't think I'm being critical, I'm merely trying to point out that you seem to have complicated yourself into a corner.
So in honour of the thought exercise: yes it could be done, probably the best [or most complicated
] way to get useable road gears
and some form of get out of jail gear, without resorting to triples is a 10 speed mtb set up on the back and 10 speed road chainset (perhaps with touring chainrings).
And the simple way to do it without a triple would probably be
1) r8000 with 34t rear cassette and whatever the smallest small ring it'll take at the front, taking into account chain wrap, or
2) look at some touring bike setups, see how they do it, and maybe have a chat with some touring specialists (SJS cycles and Spa cycles come readily to mind).
