</font><font color="blue" class="small">( Now as to those tires...should I internally ballast the turf tires or get chains for traction when snow blowing? Do they even make chains for those bad boys? )</font>
You won't need any. With a blower you don't need the same traction as with a snowplow. As to fill the rear tires... mmmm... it's a good thing for loader work (or any other earth moving job like: box blade, rear blade, etc.) but if you want to mow... I'm not sure I would do that.
KubotaOne is right about hydraulic rotator and deflector. I have both too and I wouldn't do it without them.
About the trailer, I had one: 6.5'x16'. With a 60" MMM mounted on it was tight (1.5" on each side). If you plan to get a 72" MMM, I'm not sure but maybe with the chute raised up it can fit but it's only a guess. You don't have to worry about the offset between front and rear wheels width. They share, more or less, the same line. I never had any problem getting on the trailer.