I don't know how much they've changed, but i've got the predecessor that i heard Bucks had copied, and like it for the salt. If you attach a couple of webbing straps to the shoulder straps in the back, you can lash on your rolled up raingear - you'll even forget that it's back there when it starts to rain
I'd suggest a couple of water bottle carriers that thread onto your wading belt - it's a nicer place to carry that kind of weight.
Here's an addition to your list Juro, that i carry in the back pouch - a small tupperware container for my wallet and the truck's remote control - never know when you're going to be in the suds.
While on the subject of raingear and suds, i've got a semi-dry top that has latex cuffs, a comfortable neoprene neck and a double waist with neoprene and tightening straps. If the tide has come in more than i thought, or i just think i might be in a dangerous situation, i'll don the top over my chest waders just in case i have to do some swimming. This is also when you'd want to be wearing slim neoprene boots!
Lastly, for any smokers out there, empty film cannisters are great for butts.