I don't see 16' trailer being anywhere near enough.
In fact. I'd go 24' so you have room to adjsut the load.. .. though a 20 will probably get you crammed on with the disc.
3rd ramp? make one.. or buy one. many custom sales places will sell you another ramp. I just welde dmine up. If not too wide you can get a drop deck lowboy.. just have to deal with fenders on the sides.. all depends.
On the trailer itself.. i was gonna say gooseneck.. but not with a bronco.
I personally wouldn't tow over 16' with a 1/2 ton truck anymore... I pulled way to many marginal loads way too many years. I passed 3/4 ton ( ok for most aprt ).. and went to 1 ton dually.
there's your safety margin.. thick as bread loaf. more rubber on the road. extra weight. all things that will help you whent he stuff hits the fan.
I pull a H on a 25' GN tandem deckover with flip up ramps and self cleaning beaver tail. I have a HD '3rd' ramo I can use with any of my trailers.. since the bulk of my tractors are NF rowcrops...
excess tow vehicle may be a waste.. but sure beats insufficient tow vehicle.
late model 'farm trucks' can usually be had cheap.
I tend to prefer diesel.. but a big old gasser will do.
for instance. there is a 96-96 gas f350 near me.. va, dually.. looks good.. etc. 3100$
you see this withg allthe major brands. 90's and early 00 era dualies gas and diesel for 4 digit$ and down.
good investment if you ask me.