Congratulations on your new purchase. I purchased my used 2014 XR4046 a couple of years ago - it only had 30 or so hours on it. Mine has shuttle, BH, Cab and FEL.
Just recently considering rotary mower. I've arrived at BrushBull BB72X or BB720X. With the included options the BB72X runs about 900+#'s and the BB720X runs a shade over 1400#'s. I see from the spec page that the 4046 appears to have a rated lift of 2700#'s. In the past when I've had the backhoe attached (1163#'s with 24" bucket) I've not noticed any particular issues and basically with FEL and BH attached felt like there was pretty good balance when the two are attached. That said, if my numbers are correct anyone see any issues with going with the either the weight of the BB720X or the ability of the PTO to supply enough to the BB720X to make it effective?
Again, congratulations on your purchase, everyone in my family has enjoyed using ours.