Hard Tonneau w/ Bed Bars or Roof Rack - I Need Ideas

While waiting on my 2020 DCSB TRD Off-Road to arrive, I’ve been looking at options for carrying kayaks and having more secure (and protected from the elements) bed storage. Essentially, I want to take my family camping, pack all our gear in the bed, keep it secure and out of the weather, and take the kayaks with us.
I did search, but there’s so many options out there, I just don’t know which to go with. I thought the bed crossbars may be a good solution since they’re tucked behind the cab when not hauling the kayaks. The roof rack would always be up there causing more drag.
I’ve seen the BakFlip MX4 with the KB Voodoo Cross Bars, the Diamondback (maybe just strap the boats directly to it?), Yakima roof rack, and various other combos.
Can you guys share your similar setups?

 

I’m planning on fabbing up some bed bars that have a fold-to-stow feature, like the crossbars on the OEM roof rack. They won’t be in the way when stowed, so I’ll be able to open my BakFlip G2 and do normal truck stuff. When deployed across the bed, I should be able to haul wide cargo (like a mattress) or mount an RTT.

I’m still in the design phase, so I don’t have a parts list yet. I am fairly certain I’ll be using the KB Voodoo/MAX Modular BakFlip-compatible brackets:
https://www.max-modular.com/shop-max-modular/tonneau-brackets-bakflip

And 2” or 3” quad T-slot framing:
https://www.mcmaster.com/47065T678/

Other parts, like the hinge and locking mechanism, are TBD.