Key point: I need to trust that your decisions are correct. What I want to pay for is not thinking about this and knowing that it's handled.
They do a brief interview with you over the phone, get your measurements, and send you a trunk of clothes every month. You only pay for what you keep. My friends have been very satisfied with that they've gotten.
This could exist by the way, I don't know of any off the top of my head though. Bonobos.com is the only thing that comes to mind. They're not specifically doing the above, but I think they offer a variety of fits/sizes. I've had a good experience with them in the past.
As for shops that tend to have good looking clothes, those already exist. Unfortunately full packages must be built manually from modular components, and little progress has been made on systemic solutions to this problem.
For example, I'm a big fan of Put This On:
The blog is great, and the web series is really great.
http://putthison.com/post/10287901291/put-this-on-season-one