here is what I see........
the wand holder needs to be on the outside of the opposite handle that it is on right now....
It should be about 1/3 longer then the wand tube itself and have a ball valve on the end for draining....good way to collect all the drips and can be cleaned and flushed...probably ones a week ........
the resting foot on the front of the jug should have some type of shoe for protection......it is going to take a lot of vibration and movement in the trucks
a lot of scraping...this would help save/protect this area from future leaks.....
the yellow hose will need some type of spring to help it from crimping..these types love to fold (kink) at the sprayer wand...
It could use a transport cradle like the RX-20's have to help stabilize during transport.. instead of trying to find a place to bungee cord it to.....
This could be a option and sold separate if someone wanted it......
and ..one of those cool sticky tab holders should most definitely be standard.....