Larian wants to focus the game more on the gold drop and unique loot, making you gear up on merchants. But sometimes it feels just as much RNG to try and buy something on merchants, because they have a chance of actually NOT having a piece of gear you need. I spent 4 levels without any bows upgrade because there were no merchants selling it anywhere and never droped any. So why not have fixed merchants with specialized gear? We already have them set with skillbooks anyway, just make them roll the specific gear so we have at least a chance for a small upgrade, which is better than nothing