But seriously it seems we all have our own process, there's no right or wrong way. Whatever you feel most comfortable with.
Fully agree, Brian. Many of us owners have fine-tuned their processes and they work for them - no worries.
For newbies to the trailering process there are choices to be made. Width of the trailer is likely now one of the paramount requirements! Certainly anyone can be a trailer with no side door and no winch and choose to drive it in, shimmy out the window and then do the inverse to get it out of the trailer. That process will work time and time again - and there are likely many people that do it that way - quite successfully.
The next level of convenience would be the addition of a large side-door on the trailer that permitted the GT door to be opened for far easier ingress/egress. You could still use the same drive-in/drive out process - but it is alt least easier to get in and out of car. Again, a lot of owners doing this very successfully. No problem.
IMO, the NEXT step of convenience is the ability to winch in/out. If you are setting up a trailer for this, I would recommend a rope vs cable winch and with a handheld remote control. Drive the GT to the foot of the ramp, and connect the rope, add tension. Remove parking brake. Use handheld remote to pull car in. Stop as often as needed. Stand wherever you want to have the best visibility. Move around. Make a steering adjustment if necessary. (Remember you will likely only have an inch or two of tolerance between wheel wells.) With the car in position, strap it in. Add some slack to the winch rope/cable for towing. Almost identical steps to un-load. Note that un-load is likely a far easier step.... often just requiring to hold the steering wheel straight!
The bottom line is if trailer shopping, let's assume the following (generalization);
1. Least expensive & most common: Trailer with no side door and no winch set-up but sufficient width for GT
2. More expensive: Trailer above with winch & remote capability
3. Most expensive: Trailer with large side door (but no winch)
4. Best of all worlds: Trailer with large side door and winch set-up
To summarize my opinion having direct experience with all of the above.... I would recommend 2) over 3) above if I was recommending a trailer from scratch and 4) if I had the budget.