I've noticed that despite going from 10bil in capital to 20+ bil in capital my earnings have not been increasing (with perfect trader using autotrader). Any recommendations?

I have stable 1% day from my funds (~15 bils). Level skills and standing till at least 8 to have brokers fee below 1.1% in Jita. Check if you have not distributed ISKS, if so better to switch to 20-30 minute order installation interval. Order duration may be set to 3 days. If something goes wrong with position (e.g. profitability is lost) bot will auto cancel this order. Better to split work interval in several periods with total online 12h/day.