There are many options and opinions. I don't think I have it figured out, but this is what I do currently and always seem to adjust.
The vehicle I put the emergency brake on as firmly as I can prior to putting the vehicle in park. I use heavy duty rated ratchet straps from US Cargo Control.
Ratchet Straps, Tie Down Straps, E Track Tie Downs, Cargo Straps - U.S. Cargo Control
I place an old cotton dish towel on the spoke of wheel where I put strap through so I don't scratch my chrome wheels and tighten and then go to opposite corner and repeat until all 4 tires are strapped.
I have also seen very positive reviews and when I need to buy additional I will probably buy from Mac's Custom Tie Down.
Professional Tie Down Systems for Any Vehicle
I have bought wheel bonnets and never used them, first too small and then way too hard to get over the tires and secure them due to little clearance between vehicle and trailer wall.
I have also attempted to use the trailer hitch and tow hooks on front of SUV's, they always come loose and so that didn't last long.
I use a Condor wheel chock for the Harley. I wedge my wheel chock against side wall as I load mine from a side ramp door in the front of the trailer. Wheel chock may be overkill for a trike, but I like overkill. I then use short ratchet straps around front axle with rags between the ratchet strap and axle, this is added safety and keeps front end from turning side to side. Also, be sure to use very short straps and make sure your ratchets will release without hitting the fork of your trike. The rear I use a strap through the rear wheel on each side to keep back end from side to side movement. Knock on wood I have had zero scares.
Buy a Sherline Tongue Scale, to make sure you are loaded properly.
Sherline Trailer Tongue Weight Scales
Overkill maybe for you, but I tow many different combinations in my trailer, I back the Escalade ESV in to minimize tongue weight, initial positioning of your Jeep over the axles will affect tongue weight, I mark the wall of the trailer for each vehicle so I know approximate location, I do not weigh tongue each time.
Good luck and search this forum, there is a lot of great information. Good luck and I hope I have helped!