From what I've read, loot doesn't have a big impact in the game anyway. I'd leave loot just for buildings being captured (would have been less probable to salvage something from a destroyed one), after all plundering a city would have been way more profitable than scavenging a battlefield. One gets experience from fighting and surviving already. And no need for small treasure icons to appear on the ground. Also, capturing and deleting would stop being a troll move and would make sense in many situations, just like in reality, plunder first and set ablaze later.
Although, deviating from the present game, I'd prefer if no self-destruct button was there, and one would have to destroy buildings manually (attacking them, setting them on fire, or dismantling them and getting resources back).
The best way to do this would be to remove loot in general and make units spawn (tiny amounts of) treasure when they die. Then one player (or both) has to activity gather treasure, rather than just gaining it for every kill.