You might want to try dominions 4 or conquest of Elysium 3 I think it is. Both are fairly similar style games and use individual units in combat. They gain experience and level up. You can pass out magic items to your Herod and such. The sides are all markedly different and interesting. Combat is wild and you have only the most indirect control over it. I'd say CoE has the most in common with Erf on the strategic level, but dominions is likely closer on the tactical. I will warn you that they have fairly high barriers to entry as the controls take a bit of getting used to. And the tactics... Well, good luck.