Sounds good, just be careful with the solar panels, they are made of paper, reinforcing them makes it hardier for a bit of a hit in its effeciency or you could build a foldable solar panel set or carry the parts to build a generator with a fuel stash in your vehicle and connect it with cables in a safe place to get you out of trouble before you get into trouble.

When building your vehicle sort of have an idea what you want it to do, so more tires gives you better off-road performance, try to account for any extra weight if you want to make it amphibious as it can sink if it is too heavy, if you can get your electronics skill up you can install cameras ( although it needs tweeking to work out the angles and isn't perfect) and hook up some electronics for retractable screens on windows so you can avoid enemies spotting you while still seeing where you can go

Getting your mechical up high enough for 2 engines can help with the battery drain as you could use the gas/diesel engine to charge your batteries with an alternator. I feel like solar panels feel on the weaker side to power a heavy vehicle for reliable long distance travel so it is good to plan for moments when you might run out of power. I know with advanced motor can still be a bit of a energy guzzler, but I like build my vehicles somewhat boring.

An older picture with I am not sure if it still included, Blazes Industry mod. The enhanced electric engine with just one engine still leaves me moments where I had to explore a bit while I let the batteries charge and that is almost 8 tonnes minimum it dragging around