I use a Coleman Houligan 2 tent which I chose because it's 4' tall, tall enough that I can just walk right into it and sit down. I have a Thermarest x large mattress and pillow. Typically I use a fleece sleeping bag liner for a sleeping bag, but most of my camping is done during the warmer months. If I take an early spring trip I will switch to a regular mummy bag.
Here's a link to my blog posts about bike packing:
Simply Cycle: Bike packing 101
Marc