Sonos setup recommendation for 4000 sq ft workshop with 16' walls and 27' open ceiling peak

I’m new to Sonos and am looking to setup my workshop with a Sonos system that will give smooth and immersive sound throughout.  I’m thinking potentially four Era 100 speakers in the corners at about 10’ high and either another pair of 100’s or a pair of 300’s in the middle firing towards the center. 

The workshop is 50’x80’ with 16’ walls and 27’ peaked open ceiling.  Walls are insulated metal panels so will likely have high reflectivity, but the space has relatively low to moderate slap echo.  One of the short sides is drywall with fully OSB sheeting behind and full rockwool insulation, which might explain some reduction in echo.

I’d like to be able to start with a pair or four speakers and then add to them to spread expense.  I figure I’ll eventually have to add a subwoofer as well at some point.  Not having any experience with Sonos, I’m open to suggestions about what to purchase and use in such an application.  I ordered two Era 100SL speakers to start, but could always return them if needed.  I listened to a large automotive workshop that had 8 Sonos One speakers and two subs that sounded absolutely amazing, especially at high volume levels.  I don’t need such high volume levels but would like smooth evenly distributed sound.

If anyone has experience with setting up a large space like this and could make recommendations, I would appreciate it.  Also, I’m not sure whether Era 100SL, Era 300, and potentially an Era 100 Alexa enabled speaker could all be integrated together.  Also not sure whether to run them in stereo pairs or all mono.  Please chime in with any advice.  

Cheers!