Marc,
How generous mentioning the things not to get.
Hamish, also do not get;
An old leather suitcase
A FineFare carrier bag
An old wardrobe
A Gladstone bag
An old plastic Sunblest loaf tray
An ottoman
.etc, etc.
The best thing that I have seen is still the Orvis foldey up one, I have thought about it on many occasions but very very seldom find the need to travel with tying kit.
Interested in seeing what you end up with.
In the house I keep 70% of my kit in Wham Crystal shallow shelf boxes which hold a decent amount and I can stack the nine of these on a footprint of 24" x7".
I know that you are looking for a kit bag but I'm sure that you aren't gonna get all your stuff in one bag (at least not in an orderly manner) then a smaller transport 'pocket kit' recepticle with a home storage facility might work.
Happy huntin'
Iain