While I can certainly see where you're coming from on this, I have heard quite a bit from people who play on the low population servers do so specifically BECAUSE they're low population, and as such there are benefits such as more housing, less early swarmed hunts, better MB pricing, less RMT spam, ect. While I do get that there are players on those servers that complain about long que times or poor raiding, most of the players who consider that more of a downside than the benefits have already left for other servers, or created alts on more populous servers. I don't think it would make the people currently on those servers as happy as you seem to think if they merged.....