After watching some historical battle history on YouTube I'm inspired to create a larger scale conflict, but it might be best to have it as a nation roleplay without fancy numbers, just pitting together armies that sounds right for what you have in mind. It could maybe fit in arena if it was just single large scale battles, but not sure what others would think about that.

Some historical battles are sort of baffling. Like, I wouldn't be surprised if you said the Roman Empire lost 5 legions fighting three farmers with a stick. It's amazing they lasted as long as they did when quite a few battles seems par for the course that they loose thousands of soldiers and can't  even put up a fight. 

Having a persistent world focused on the battles, and interesting outcomes and alliances, could be a blast. Anyone interested? It would be fantasy with really low level magic. Realistic battle plans are to be used, even if we get cool new units like Pegasus.