There are reasons some people have more than one bike - because no single bike can do everything perfectly. I guess most Brommie riders use them in cities and are not riding daily more than 20 miles max. Yes, some people do decide to do longer rides but I doubt they are the bulk of Brompton owners. Brompton markets toward the multi-modal fast fold crowd, not the comfy long distance tourer.

Get a Birdy if you want to tour with suspension and a halfway decent fold. Or put the trekking bars on your Brompton and some cushy tape and buy some gel gloves and call it a day, lol.