You will probably have a few people jump on here soon telling you about the frame warranty. My opinion though, do what works for you. I'll be posting my changes to the rear end of our Silverback in the near future. Stock bumper is fixing to come off of ours, and I'll post what we're doing in a few months when I actually get time to start burning wire. Got the steel, just need the time.
I like what you've done. Ours is a similar concept with receiver tubes. Most will appear stock at a glance. It will be a multi use set up, but mainly for bikes.
John and Rebecca Dickson
Emma-7 / Little John-5 / Iva-1
Full Timing Again, Rev B
2013 Ford F-350 Lariat CC LB PSD
2015 SOB TT - With OC's Awning Poles (#8)
At least in Heaven, RVs will be perfect, and I won't have to keep fixing them.