To beat THIS IS SPARTA Without anyone getting halfway to your base is to build 3 quake boxes and fully upgrade them, then make as many gunmen as you can, just sit back and watch
You should never do the quests until you have the best stuff and a vanguard, everyone has one, Buccaneers and Enforcers. the enemies should be weak at the start
If you are delivering a package in the enforcers guild mission, you encounter alot of guys, my speed was at 20x so I'd skip right past some of them, but near the end i was challenged but the buttons were gone