With that in mind, id like to address the comment by the user Epythymy. I dont think the problems are that glaring.

1st, "things out of thin air" are not questioned because people of the original world (scholar and his entourage) have never seen MC materialise things out of thin air and they saw his village and the oasis for the first time. The jackalans dont need explanation as they are low iq creatures. The only one, who might have had questions is the guide/captain who escorted him to the oasis before, but that dude is a minor character who we will probably never hear from again, unless the author would like to revisit him and address this "glaring" logical hole.

2nd is the "For Swardia" (a kindom faction within mount&blade) shout. They are mc's private forces who are foreign to the dukedom, even if they actually shouted "For Demacia" or even something in Turkish, why would natives care.

3rd, "the perks appear during crisis", that's what novels with cheat codes are about lol, plus they all have a cause and effect, the fact that readers may forget about something is not really a logical fallacy, but rather a sad testament to our generation's fish-like attention span. And I would further argue that the items appear before a crisis or when there is a specific need for plot development. All I can say is that this system is really user friendly lol. However, these perks dont make the novel boring due to the fact of how overwhelming the odds are against mc: in the dessert, outnumbered, sandwiched between 2 hostile kingdoms, etc.

4th, "character idiocity and boring action sequences with nothing but simple ambush". Well, mc's first fight of taking the oasis did include some decent tactics in my opinion, considering it was the beginning of the novel. The scheme to get the unwilling knights to fight the battle, the use of setting sun for vision control, and an ambush before the dusk are all what I consider to be an interesting strategic fight. The dumb general and dumber MC did come up with a battle plan for 300 vs 2000+, that included a fire attack, a night raid, a decapitation strike, a plalanx charge, etc. The mobility and range advantage mentioned consisted of less than 20 cavalry and 3 volleys of 500 arrows (cursed system perks lol). Maybe mortals like me just cant see the grand opportunities that brilliant strategists can, not sure, though I have to admit that regretably, I couldnt find the yt videos of monkeys fighting with sticks, but it does sound impressive.