At what point is it necessary to run ladder line Vs coax to a horizontal loop

I'm setting up a 40m full wave loop over my roof and I'm conflicted about how to run feed line to it. I have it connected directly to a 4:1 balun with choke (my post history has info) and my ft710 currently tunes it just fine on 40 through 10 meters. I'm going to raise it up onto a 10' mast to get it off the roof itself. It's a short run, about 6 feet up from my desk on the second floor through the ceiling, 10' from there through an attic vent, and about another 15' up the mast from there. I understand the reasoning behind feeding loops with ladder line but if the SWR isn't terrible and I'm only running 45 feet, should I bother with it?

Also, since grounding questions never end, how should a setup like this be grounded?