We're one the same page there, I'll be going flatbed as well w/ the front wall removed on the bed so the camper can sit closer to the cab. I'm thinking 7-7.5' long main camper on my shortbox. My current hawk is ~6'-8"or9" long and without a front on the flatbed I think I can move the camper ~3" forward so a 7' camper would be the same length as my current one and a 7.5' would only be 6" longer which I can live with.
If I do it I'd be planning on doing the build myself and current figures are looking like I could pull it off w/ one of the more affordable aluminum flatbeds for around $10k.
Currently debating interior plans: Either a side entry door near the front of the camper with a 40" wide dinette across the back that turns into a twin bed and ~4' long counter opposite the door (fridge along the front on the other side of the doorway). Or rear entry with a long isle way, 20" wide dinettes on either side (facing back to front) with 2'-2.5' long counters on either side of the front of the camper. The dinettes would be ~5' long and turn into single width beds and there would be an 18" foot box for the beds build into the cabinets (under the counter) to make 6.5' long single beds.
Either option would also have a cab over bed. Main goal is better use of space to accommodate 2 adults and 2 kids. Also better thermal insulation.
My main goal is to increase storage. I'm tired of all my gear being in a pile in the middle of the camper. I'm still nailing down the details but one thing is for sure: the door is going on the side. That will free up the back wall for bikes, fuel cans, or anything else i want to bolt to the outside.