Is anybody else just not… good?

I have around 275 hours in the WH3, and frankly I rarely do any better than the autoresolve. Basically the only time I can consistently beat the autoresolve is when I’m doing a siege with a lot of artillery, and then I just bury them in hellstorm rockets. I’m playing in normal/normal, too. How can I get better? I usually play empire, FWIW.