I have the tools I normally carry in my truck (TV). A little everything, cheap little socket set, good quality
#2 phillips and flat head, good Multimeter, connectors, etc..
Make sure you have an appropriate jack, I have a 12 ton bottle jack, lug wrench, and torque wrench with sockets to fit my lugs and WDH. Make sure you check to mske sure they fit and work when you need them. I put them in the TT on the right side where I can access them easy if I get a flat. 90% of the time you will pull to the right to change a tire. I don't want to put my blind back to traffic while digging in a compartment.
If I don't have a tool I need, chances are it is a tool that I probably won't use again, but can go somewhere and get it if needed. I don't want to carry something I will hardly use. All weight counts. Think about multi-tools like screw drivers where you change tips, wrenches with different sizes on each end, etc..
Just my thoughts. So far have always had what I need and often what someone else needs.