Cool idea,

Personaly I would go for an old (partially stripped) motorhome, bit more load capacity and selfdriven and quicker to setup at location. Less hasstle hooking up and on the road.
Advantage of caravan(trailer) can leve it behind and drive around the towing vehicle or switch it.

You have obviously put significant time and thought into this, and based on your current work flow set up from the back of your van, this would likely be a slight improvement by resolving and streamlining some of the issues you are be having now, which only you know what they are.
As such, any suggestions and/or comments are merely observational and may not truly reflect what you are setting out to achieve or have the budget to accomplish.
So having prefaced that, my first comment would be that it looks rather cramped in there... If at all possible I would suggest a "walk through" sized van or trailer where you could also reinforce the roof so that it could also be used as a platform for an elevated camera when possible. I can only assume the bubble on the roof is not a sunroof (too much light for a control room) but an air conditioner (which would be a necessity on a hot summer day beside the football pitch). I would also suggest a slightly insulated interior, especially if there is a generator anywhere nearby that you are using for power.
All-in-all though, I think it's a great idea. Keep us posted as to how you make out!


Ice

On outdoor events , we always use my van or a caravan as our studio.

I does tend to get hot, but since it's a small volume of air you can cool it quite easy. If it's very hot i use ducting to force aircon air through equipment before it cools me
(i can cool myself with cold beverages, systems can't :) )

m@ik

Looks nice, but useless with rain etc...

What is the small mixer at the right on the first pictures? I saw it a couple of times here..
Thank you!

And MIDI controllers will have their keys on the list at the Shortcuts menu? Or requires any software to redirect?