I assume that 5595 number your quoting is dry or shipping weight. No one will ever tow a trailer thst actually scales even close to that number. Look for the trailers GVWR and base your tow vehicle off that. You can find the trailers GVWR by looking at the tag near the left front corner of the trailer. It offers a world of useful information.
As to towing ability.
The 1500 ecodiesel gets great fuel economy, but has really low towing ratings. It is not the best pick for towing.
Ford F150 ecoboost can be configured to tow heavy, but costs to do so it winds up almost cheaper to go to a 2500
As far as differences. That has been espounded many times. Basically larger brakes, stronger frames, tires, wheels, not to mention load ratings. The new Rams with rear coil springs? Not heard any negative comments. Spring rates are going to be same or similar between leaf and coils. So I see no reason to worry about that.
Ride? Yea a 1500 should in theory ride a bit better than a comparable 2500. But most people wont see the difference.