I have this conversation quite regularly. Its either one of my students or a random person I meet. "I own ..... and I want to mod the suspension/engine".
First rule on modifying anything, start with the correct chassis.
You can build anything into anything with enough money. If you cant find the correct parts to do whatever it is you want to do, there's probably a good reason.
Stronger tires would be a good start but, can your steering hold up to moderate dirt roads, how about ball joints? Just because it hasn't broken yet doesn't mean its a good choice. I'm sure your probably aware that any of these things means more maintenance. Having custom suspension built means your the first and you get to run with a prototype. That hardly ends well.
Aside from all that, does your vehicle have struts on all 4 corners? If so, small spacers will get you some lift. Remember, ball joints have a range of motion. Exceed that and they fail. An .5-1 inch may be all you can get safely. If its a coil spring/trailing arm rear, you can still space them with a trailing arm rear being the most forgiving. Just be careful on the front. Measure things, do a bit of research and you may find something that will fit.
As I mentioned, I have this conversation regularly and my answer is always the same. Figure out what you want to do and buy a common vehicle. You want something someone else has already done the math on and parts are plentiful. When I'm asked about building track cars by someone who has never raced, I point them at a Miata. Why? Good chassis and a ton of parts available to mod it. Build and drive something common then decide where to go from there.