That is a bit of a mess. A couple of additional suggestions:
It looks like the fuse holder with the 20A is on the wire to the breakaway switch. Anyone ever seen a fuse on a breakaway? Seems to me that this is wrong! If your trailer breaks away, you want full power to the brakes stopping the trailer. If they draw too much current for some reason, and the fuse blows, no e-brakes at all.
The wire for the main disconnect fuse (missing) seems awfully small gauge. For a pup trailer, I would expect that this would be a 20A fuse most likely, but that is a pretty small gauge wire for 20A. Wondering if the wire would melt before the fuse blew... I'd be wanting to upgrade that.
I'm also wondering where the battery box mounts on here. If it is in front of the LPG tank, it doesn't look like those wires will reach?
2011 Jayco X19H (purchased 2015)
2008 Jayco 1007 PUP (purchased new, traded for the X19)
2012 Chev Traverse LT with TP