So some elemental games I have a re fun and some are ridicules (like wiping an NPC civ out in the first 15 turns). Though some testing I came up with sort of a formula that generally creates interesting and fun games, if you have some as well share them.
 

Difficulty: Challenging (map/race)

Map Size: Large

Number of NPC Races: 3

Races: 2 trading races + 1 war race (for a more casual trading type game) or 2 war race + 1 trade race for a more combat oriented game (or any combo). For an extra challenge chose Empire NPCs since they can get ogre troops which are tough (and you are playing kingdom).

The large map with 3 NPC races usually spreads the races apart more which lets the AI build up a bit before they encounter the player which usually means they have troops to defend and attack.
I've actually been in a war where border towns were taken and retaken several times and the Ai gave me a nice challenge (till I captured their ogre camp).

If anyone else has some good tips, post them.