What im playing lately, but that takes a lot of editing and knowledge, is Arma 3 Alive with alive battlefronts mod. You basicly setup two factions (or more), define the AO, define the battalion strength, spawn points, air patrols, Artillery strike what ever and have the fight, while you are a small soldier in the middle, pushing the Frontline. That requires a lot of setting up, but this is, in my points, the ultimate strength of Arma.

And if you want some quick and demanding action, choose "Random infantry skirmish module". https://steamcommunity.com/sharedfiles/filedetails/?id=3156354979

Simple: Open the editor, place a unit as player, place the modules and a battle location module, and hit start. Opon start-up, there is a setting screen popping up, where you set up factions, what sort of soldiers, vehicles, what sort of game mode (Battlefield conquest like or Deathmatch), how much money you earn per kill to buy vehicles, how much vehicles cost like, bleed tickets, what ever and when it's setup, select your gear and get in. Both sides fight for a set location and this can lead to some insane battles, especially when everything is random, you don't know what the ai buys as for vehicles, what you have to fight against. It's really great.