Bigger BP TH's - pros and cons

Having towed a 27 foot BP TH and now on my second 35 foot 5er TH, I would be very concerned about that long (35 foot) BP TH. Bumper pull toy haulers of any size are extremely sensitive to loading. Depending on the toys and where your water tank(s) are, it can be difficult to get enough weight on the hitch to make them tow reasonably well. With my 27 foot BP TH, if I didn't carry at least 100 gallons of water, I had to put my ATV in the back of the pickup in order to keep the trailer balanced properly for towing. Another factor to consider is the loaded hitch weight and the payload capacity of your truck. I think that when loaded for a trip, you may be looking at more weight than your truck can handle. BPs can be a little easier to maneuver than 5th wheels in tight spots, but for me, that is the only advantage of a 5er over a BP.
You have a lot of research to do.