My goodness, you've gone all out! I just use a simple heavy-duty twist-tie and tie the 4" hose off to the right-side handle. That keeps the hose well out of the way without tieing up any extra fittings. This issue is, IMHO, the only real design flaw in the DW735... I don't know how DeWalt missed that their exhaust location leaves the hose draped over the outfeed table!
I do something similar but I have a 6" hose. I use bungee cords to hold the 6" PVC fitting over the dust port. I used to use the special connector but my DC broke it off before. I've been tempted to cut a 6" hole in the top of the 735 to connect my 6" hose, but haven't had the guts to do that yet.