If bandwidth is cheaper, the rule is to flatten your networks out. This would link to the WAN through one special switch designed to provide wide-area connections for the community. Where the number of workgroup switches prevents full meshing, a second tier of switches of limited size can be used to create the network. Such a LAN has fewer devices than the traditional structure, and lower latency because there's less handling of packets. You'll note that I said WAN connections would be made through a special switch.
Switches are cheaper, and routers are best at managing congested links and finding alternate paths.
Alternate routes are key to reliability in a complex public network like the Internet, but most company networks won't have many alternative paths to choose from. That leaves congestion management to justify conventional routers.