Look at Stehl, Acme Eze-Tow, Master Tow, Kar Kaddy SS, Roadmaster, etc. There are a number that will probably fit your needs. Also, do a search here and you will find a bunch of info.
We went with one from Landgrebe Mgf (towtrailer.com) because they could build one to our specs that fit our larger suv. We needed a wider width and heavier capacity and they were the only ones that could accomodate both needs. We found several wide enough but the load capacity was short. Not sure about the low clearance but there is only 8'" clearance on our car measuring from the ground to the bottom of the front spoiler. I don't have the dolly yet but have been assured it will not be a problem.
I went with electric brakes because that is what Landgrebe advised me to do. We spend several weeks each summer in the Colorado Rockies and their advice was surge would work fine under many circustances but electric is better for steeper grades.
Electric brakes will only interact with your brake controller. If you have it wired to you brake pedal light wire the exhaust brake should not affect it. With surge you could get some braking with the exhaust if there is enough pressure on the actuator on the dolly.
2013 Excel Winslow 34RKM
2015 GMC 3500 Denali Duramax 4X4 dually