Would you like to see a boss release?

Depends. I don't really want to face overworld bosses that are already present; I like the idea of constructing the boss or going to a new region (like the End) to fight a boss. And there are already plenty of mods that offer bosses, and some command block creations that create bosses in vanilla Minecraft.

 

Specially created bosses on some servers are very interesting. I recommend you try new servers and mods

 

You don't need new servers or mods to experience bosses that other people have made. Sometimes all it takes is a command block, and sometimes a resource pack (if you want to change the visuals and sounds to create a new experience). For instance, there's the Herobrine Boss for Minecraft 1.8.1 that just requires pasting a long command into a command block.