As it sounds like you are just getting started, don't underestimate the role tires and tire pressure can play in easing your pain and improving the overall ride quality for your team. Noticing you folks have a Samba, which has 26" wheels, affords lots of options. And wider is not always more comfortable depending on the tires' design and inflation. Though not for everyone, we sure get a much better ride on Compass offerings.
They have a two in 26".