There is no better chassis to start with than a free one!!
Some of us build certain chassis for the wheelbase. Some build others because they are easy to build. Some build because not very many people race a certain chassis, and were tired of looking at MTDs, Murray's and Craftsman. Lol
Some people build what they have.
Your reasons for building are the best. I wouldn't be doing what I am now if my Dad hadn't stuck a wrench in my hand. And you'll never get back the time you don't spend with your kids. I spent most of my children's younger years just trying to keep a roof over them and food in them. Take it from someone who knows, you can replace the memories you don't have with your children, it's replaced with regret and sorrow that just like memories you carry with you for life!!