I find it rather ridiculous that basic skirmishers, some of the cheapest units in the game, can easily bring down a massive number of elephants.

But they artillery are worse. They are extremely expensive, slow on the campaign map, and nearly worthless on the battlefield. But they are best used in sieges, you say. Well, you can build a few ladders and assault towers in their place for free! The cost of artillery far outweighs their use. Does anyone seriously use artillery in EB?