I did feel the same that if I followed the main story in a realistic way, I would have no time developing my skills enough for a battle against Runt. I had only mail armor when facing Runt’s army in my first playthrough, and did not manage to sabotage anything beforehand. It was tough for me, especially the archer part. As for Runt, he is a boss so that I expected to die a lot. Fortunately I got an autosave just before the battle.
To be honest, I felt the same for many games. In my very first Baldur’s Gate playthrough, when I reached the final battle, my hightest-level character was Imeon, at merely level 7. All the other members are level 6 or less. My entire squad was nearly wiped out by a single cloudkill spell, which has a chance to instantly kill any character that are equal or less than level 6.
But on the other hand, when I found my Henry can heal himself in a night’s sleep, I told myself, ‘well, this game is realistic, but still a game, afterall.’ And later I discovered that, Henry is even able to heal with the marigold potion, which is easy to made, with marigold being everywhere and cheap, and the it takes effect in a matter of munites.
As a result, in my second playthourgh, I played KCD more like a regular game. Though in hardcore mode I got penalties in serveral aspects, the overall difficultiy dropped dramatically. A lot of players call the ‘softcore’ version already hardcore for a reason. My point being, a hardcore video game has to find a balance between hardcore and fun.