I do want to try the Alex campaign, especially if you say it was tougher (although I don't really care for the Berserks as enemies.. a bunch of glass cannons you either kill very quickly or die very quickly). Even on hard the MSF route wasn't much challenge after I got the shield upgrades, antimissile and repairs fully upgraded with system 3 and laser turrets. You rarely need to undock your fighters, just turn on 4X and wait. After getting the Lion it was truly pointless. The hardest part was definitively the beginning of the game.
I guess that is often a flaw in RPG like designs. You either screw up your build and have a difficult time or you get too optimized and there is no challenge.
Maybe I'll hack the game files and really see if I can win with a Mastiff!