Okay, I see we're getting off topic here. The original purpose of this post, from what I read, was how to address the many problems occurring with the massive amounts of guests.
Yes, guests are treated poorly. I don't talk on chat much, I mainly mind my own business creating my projects. However, when I happen to read, when a guests seems sincerely confused or lost in how to play, people either ignore them or talk down on them. This is unacceptable, in my opinion.
As to the lag issue. Lag isn't so much the problem with how many people we have online. It's the "How many people in a certain area" problem. When I go to /spawn and face toward people, I get SO laggy (10-20 fps). If I face away from them, I go back to my 80 fps. Out in the middle of nowhere, where I am doing my projects, I get as low as 70 fps, and as high as 94.
I have a GREAT internet connection. I attend a university and live on campus, where my connection is "state of the art." We just had a major upgrade in internet over the summer. So my connection is not a problem.
The easiest fix is like Drewlsgod, have many signs in the GW warping guests to different areas in the GW. This will decrease laggy screens. As to fixing the timing issue, I believe Notch said in 1.9 that servers will be able to handle more people without as much lag. As well, if you people really want to blame lag, blame the applications that aren't functioning properly. Sawine and admins and are working to fix all the bugs. Once all the bugs are fixed, I'm sure we can handle about 80 people with 0% lag.
As well, some of the timing issues (block lag, for example) is caused by there being too much information around you (i.e. people, lava/water structures, portals, anything that takes a lot of cpu/internet).
We need guests to survive as a server. Yes, I admit we are growing MUCH TOO FAST in my opinion, however growing fast is better than not growing at all.
As well, I believe there is a way to allocate RAM to specific things? Why not allocate the majority of the RAM on the server to the main world? This way, the RAM is then divided between the two worlds, and will hopefully create less lag. This is just my suggestion, and I know it'll probably be shot down.
Thanks for reading guys. Have a good day.