Wolf Tooth B Rad mounting system with mini-roll top bag will fit your tube, flat kit, CO2, levers, mini-tool, etc and this can be mounted inside your frame triangle. I've used mine on my seat tube and positioned to have the tool bag just below the water bottle, but you may need to play around with placement.
https://www.wolftoothcomponents.com/...s/b-rad-system
I'd get a mount for the mini-pump and attach it to the downtube bottle bosses. Something like this:
https://ride.lezyne.com/products/1-rp-brkt-v1nhpmp
I have no idea how big that water filter and bladder are, but maybe they can fit into a saddle bag?
