Did this a while back, playing with isometric 3D and then painting a ton over. It was a good study in what shortcuts to use 3D for and what to do by hand in the interest of speed.
I'm really excited for Satellite Reign to come out, I backed their Kickstarter and am totally in awe of the art they've released so far. You can still donate for packages on their website if you missed the original campaign. It's the spiritual sequel to Syndicate (EA has the IP locked away for themselves) by a lot of the original developers. If you loved the originals (90s power!) this looks to be everything you'd want in an updated reboot (unlike EA FPS reboot, great sci-fi shooter, just not Syndicate)
Check it out: SATELLITE REIGN