I lost interest, so it took a while:
This is the very essence of "UFO: Enemy Unknown/X-COM: UFO Defense" the original game! Did you try vanilla openxcom? Did you like it? If you are not proficient with vanilla, you'll most likely have a hard time with X-Piratez.
I played Vanilla and OpenXCom many times. I love them, because they're a unique genre all by themselves (UFO and TFTD). Yes, the aliens are very accurate and hit hard, so I expect to lose multiple soldiers every mission. It's part of the game, and they're easily replaceable. The main difference between a rookie and an officer is the morale gained, or lost when killed. And I always sack every soldier with less than 40-50 morale.
There is easy replacement of gals, all it takes is cash. Perhaps you have neglected some early research topics.
In Piratez, the replacement soldiers are hard to get or useless wimps. Yes, even the extremely expensive veterans and freaks. The freaks get *ONE* stat that is on par with a Lunatic, and all the other ones will never get good.
There are plenty of lethal weapons some of which are available from the very beginning. Don't expect all your gals to be toting heavy plasma 3 months in like vanilla. Just because you can't research a weapon yet, doesn't automatically mean you can't use it. Advanced armors probably takes the longest to get your gals equipped, just like the OG. But the early armors are useful.
Don't be afraid to skip or abort missions where the odds are heavily stacked against you. Try to do the high scoring ones; it will take some experience to figure out which score well.
Well, in the third month or so, the enemy simply nuked all but two of my gals. BOOM! Now, three years in, I still haven't got anything even half as lethal.
And while chain mail is cool for the first two years, it doesn't make much difference afterwards. Your gals still melt after a single attack, if it is more dangerous than civilians.
And, yes, I aborted more than half the missions because they were hopeless. Not in the least because I couldn't afford to lose the gals and hardware.
In Piratez, losing gals and equipment is punished harshly and improvement is extremely glacial. Which is the opposite of what made the originals the classics they are.
In the originals I research laser weapons and I can take on the aliens on equal terms. In Piratez, I research thousands of things that sound cool but require tens of requisites and are obsolete the moment they are available. My gals get comparatively weaker all the time.
It's probably fun if you spend a few years learning the optimal research route and just like to play the same few battles again, again, again and again, while you get weaker if the RNG doesn't give you one of the requisites. But who cares, if you lose, you start a new game that is going to take half a year to finish.
I like replayability and diversity, but I'm no masochist.
Then again, the Quickmind let's play shows that melee is very powerful. Throw your weapons and armor away, they will only hamper you! It's like a Japanese game, where a Katana beats a nuke, and a single, unarmed combatant slaughters battalions of soldiers armed with firearms.