So as a businessman I've been doing great overall, but over the years I've started to notice that taxes eat a pretty big chunk of my profit. Can I reduce them legally to increase my effective revenue, or is the only strategy growing until I'm satisfied with the money I'm making?

Of course you can, it's a whole industry called tax optimization. If you want to learn more about this, consult Osome, here's their company webpage. They help businesses of all sizes to register in UK for reduced taxation and government subsidies. I think you will appreciate this, since it's just what you've been looking for and even more.