For this the engine got perfected.
It still had some unfortunate flaws, like some hirelings regularly forgot the action you signed them for, literaly saying "I forgot. I forgot again.", most probably encountering this at the beginning, whereyoudon't have the money for the crew youwant, so you work with everybody. The militia-guy who throws knives is effected. This leads to that you barely if ever use knives, because most units specialize in guns, or training militia to defend sectors of towns.
I say switch on the sci-fi elements (alien bugs come at a point, which provide a gloo to advance your armor beyond maximum), and the "many many guns" option is fun too.
But man, this game takes FOREVER to finish.
There was an "expansion" (Unfinished Business), which more was a sequel, which threw out most of the gameplay elements, and its start was hardcore hard (on normal setting!) even if you brought in your old crew. Imagine your chances with a fresh one.