The learning curve for the game is extremely high, but once you know a few general tips, you should be set.
Rules are:
1. Level your hero up as fast as you can. If you are a mage, Evoker + Fire destroys everything.
2. Fire > Air > Earth > Water
3. Armor is VERY important.
4. Build troops early, don't wait for economic expansion
5. Don't build cheap troops, they are virtually useless.
6. Don't over extend with your towns/outposts. It is better to have 4 defended towns than 6 undefended ones.
Now granted, there is without a doubt a huge balancing issue based on the above rules.