why not a 38 or 39 or even 33T single up front? my commuter is a 1x7 with a 33 up front and an 11-28 8 speed in the back with the smallest cog locked out due to frame clearance. it has a really low gear, is very simple to setup, adjust, and maintain, and the highest gear will still get it to 25mph, which is more than I need when loaded or towing a trailer.