1. I kind of agree, the thugs stop showing up a bit too soon. My advice would be to shield up and wise up. Always target the poleweapons users, then the 2handers. Make good use of your poleweapons, they have pretty good damage, and i give them to my most skilled fighters in the beginning. If your frontline is weak, focus on holding the enemy for the backline to punish. Losing someone at the beginning is pretty common, even if you have a good strategy. Sometimes shit happens, the enemy does critical damage… I focus on buying armor at the start, trying to give more durability to my brothers. And SHIELDS, don’t forget the shields. I start using the 2hander, but sparingly – keep him back for a bit, then hit hard before he can be crippled.
2. Bad luck. I prefer 1-skull quests to raze bases, or to hunt down what is terrorizing a village/town.
3. You were doing it correctly, it’s good to have a different range of weapons to choose from – different shields too. But against heavy armor, i prefer hammers and axes. I, personally, think maces are a little shitty – not enough armor damage to me, and that was their main function in real life. What i said before, focus on the most dangerous guys – that includes the flailman when you have lousy headgear.
4. Actually, that might be your biggest problem IMO. I focus on getting a LOT of guys. I even recruit cripples. You know why? Meatshields, cannon fodder – every army needs it. Even if they can’t hit anything, they soak up damage that would be done to your good brothers. The enemy chooses the target he has the biggest chance of hitting. Give them their targets, then make them pay for it. Numerical advantage also helps in surrounding enemies, and you can use the lousy brothers to break their shields, if you have axes to spare. 100% hit change for Split Shield. Abuse it. I try to buy a little bit of gear whenever there is something cheap – damaged sometimes – and i have spare cash. I always begin the upgrades by the armor – weapons i mainly take from the enemy.
5. RNJesus. You can retreat or try to make the enemy chase you. Combat is unpredictable and punishing in real life, and so it is in Battle Brothers. Have that shitty brothers to attract arrows, bolts and thrown weapons. Accept the losses, they are unavoidable sometimes. I’ve lost many a promising recruit. I always have new recruits, sometimes they succeed, most times they die horribly. Mostly, they are the ones that bite the dust when things go sour. Ah, the fine life of a mercenary! Which combat to avoid? I really hate the damned goblins, and fights against enemies with ranged superiority can be really painful.
With practice, you will improve, and will stop making some silly mistakes that you end up paying dearly for.
Best of luck