As of right now, the most comfortable bass I own is a Peavey Grind. I can talk lots about why I like this bass, but I'll keep it to ergonomics for the sake of this thread. The body is perfectly balanced in between both strap buttons, so I can have the neck tilted up upward without the need to lift it with my left hand. The neck is very very comfortable and has a flat finish that is perfect for sliding. The body has all the right curves in all the right places, so it's pretty comfortable to play for hours. Lastly, it is pretty light to the point that I forget how long I have been playing it. It is a relatively cheap, but lovely bass indeed.