My main commuter is now a Birdy folding bike which came with 1x7 gearing. 18" wheels, 11-28 cass, 52t chainring.

It was pretty decent for my commute, although there are some stretches where there's not enough gearing, other parts where lower gearing would be nice. Not a deal-breaker by any means.

Except the guy I bought the bike from offered up a Sachs Dual Drive rear wheel...

And so now it is 3x7, with the 3 in the hub...