Actually, SCX doesn't really hit harder :) one critical factor of weapons that is missing from in game description is damage reduction with range. That's why HC Blasters and Fusion weapons are basically useless. And yes, game manual lies multiple times ;)
After I realized the basic principles, game became easy. But it's important to note, in the third system only Gehenna is playable. Acheron is very difficult, and Charon is impossible.
I always go for the best, longest range weapons. So, SP 1200 laser - probably the best anti shield weapon in the game, EMP Blaster, shorter range, only damages shields, but also fires twice so in some cases is even better, add HK missiles, particle guns and some heavy cannons and watch the carnage. And there is really no reason to use any hercs apart from heaviest available plus few scouts... unless someone wants a challange like sending single machine on a difficult mission, Ogre with ELF weapons, including mortars, can offer completely different experience.
Great game, BTW.