The concourses originally felt more cramped, but the airport spent a lot of money to make the concourse gate areas a lot more airy.

This blog post shows kind of a before/after picture of the changes... https://bylandandsea.me/2021/06/big-...t-concourse-b/

I don't travel nearly as much as most of the people on FT, but I've never had issues with the train, and security has been a breeze. I can usually get off the parking lot shuttle bus and be at my gate within 10-20 minutes--depending how far down the concourse I need to walk.