Jimbroth viewing women as property makes sense by the end when he casually advises Carl now trapped in Skyguard to get married to an NPC. Operating on video game logic, NPCs are kind of like property and, since most players are guys, most of the NPCs that can be married to the player's character would be women.
Carl's failure to learn his lesson is foreshadowed a lot. When Jimbroth first arrives, Carl's main concern is to continue the game rather than marvel that his game character came to life. He sees a pendant as only as good as the stat gains, and as such doesn't see the meaning behind Jimbroth giving it to Jessica. He has expensive wines and food that he never drinks or eats. Simply to put, Carl's major problem was never the game, but his selfishness and lack of empathy towards others. He wants things, but for himself to hoard rather than share with his friends.
The reason everybody immediately loves Jimbroth might be because he has a very high speechcraft.
Jimbroth being optimized to impress Carl's boss and girlfriend makes perfect sense since the amulet scene reveals Carl is a lousy roleplayer. He would simply have played as a fantasy version of himself with everything he feels specifically self-conscious about reversed.
The ending reveals that the characters in Skyguard feel pain when they die. Given how advanced Jimbroth is, how many times did he "die" while Carl was playing?
