Grandpa:
I see no reason you can't car top your TI, we did it for 4 yrs every single weekend (sometimes 2-3 times per weekend). Here is a pic of our setup.
Especially with a pickup, and ladder rack it will be much easier than my setup.
The main two reasons we car topped are:
1: we have a camper that we toe behind our Denali (using the hitch) so the only place left is the roof, and we are not about to go camping without our kayaks (we have over 250,000 road miles with kayaks on the roof since 2007, haven't lost any yet (lol)).
2: Our house in Key West has no place to put a trailer (parking is a premium in Key West), if we were to have a trailer down there it costs $2.50/hr to park your car, and another $2.50/hr to park your trailer pretty much anyplace on the Island (that is if you can even find trailer parking at all (at Simonton st boat ramp they have 3 metered trailer parking slots, you have to park your car somewhere else ), that's it on that entire side of the Island, unless you want to go miles north far away from anything of interest.
I'm not a big guy 5'8" 230 lbs in my mid 60's and not particularly fit at all. However we are long time kayakers (mostly Hobies) and my wife and I actually prefer tandem kayaks vs having to setup two complete singles every time we go out (one tandem is easier in our opinion, plus it looks bad when I leave her behind 5 miles from launch because she is tired (lol)). All tandem kayaks are large and cumbersome when compared to singles, and we are used to this. To be honest it is actually easier to load our TI on our roof than it ever was loading our old Oasis. The old Oasis had no handles of any kind and nothing to grab onto, I got hurt a few times loading/unloading the Oasis. Once we got the TI it has plenty of hand holds to grab, is only a few lbs heavier (since you only ever lift half the kayak, the weight difference was 50 lbs (TI hull) vs 45 lbs (Oasis), and the extra couple feet in length of the TI actually makes it much easier to lift half the boat.
The only downside to car topping is the setup time, I have extra sails, and motors on my TI because I mostly use the boat offshore so setup time when car topping is an hour.
Last year I did go out and buy a cheap Harbor Freight steel utility trailer ($140 bucks on sale), I modified and extended it with some aluminum, and PVC bunks (the PVC cost around $15 bucks) vs the Hobie cradles (around $250) which I simply couldn't afford. I have a couple hundred more in aluminum and a couple weekends of my time working on it in the garage, my only tools we an electric drill and a hack saw.
Now locally in Sarasota I pretty much only use the trailer, and store the boat fully rigged in the garage, it takes me 15 minutes to launch, and a lot easier, everything is just stored in the boat in the garage (ie.. motors, sails, rigging, anchor system, etc) and it only takes 2 minutes to roll out of the garage and hook up to the car. Life is good.
One other little note about car topping in salt water, I rusted out the roof on our Denali and it had to be replaced, because of the salt water, I have since been banned from using the Denali (my wifes car) for anything boat related (thus the trailer).
Here is a pic of my cheap harbor freight trailer setup. Of course it's a piece of junk and will likely rust out in 5 years, but who cares, it works..... I'm not about to win a beauty contest, I just want to get the boat to the water and back.
You have a ton of options.
Good luck
Bob