This isn't really a cheat, it's more off a guide.

I had a lot of trouble finishing this game on hard, but then I found a really easy way to do it.

Don't rush your way through the game because you are going to come across enemies that are high levels.

Wait until you are about level 20 - 25, before you carry on into the harder levels.

The best way to do this is to complete as many faction and side missions as you can.

It really helps!