Sadly the way the game is right now, you pretty much have Bandits ranging from levels 1 to 20+, which is indescribably stupid, same for a lot of monsters, though I already went indepth with this exact same point.
I will say that the whole concept of "levels" and "health" as it is applied currently in the game, doesn't fit at all. This isn't Skyrim, their world difficulty heatmap is all screwed up and sadly they aren't as experienced at making games yet to fully grasp how to design things such as weapons in an open world game. For a good example that many a familiar with, look at Fallout New Vegas and the way it handles weapons and itemization in relation to enemy toughness.
I'm starting to want to make that heatmap again, would certainly save me the trouble of typing stuff up while trying to explain relatively simple game design concepts.
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I do seriously hope you're not suggesting that you're ok with the idea of a single monster type having a level variance that ranges from level 1 to the high teens, right?