Teaparty is easily the best map, and arguably the only good map.
Most other maps have horrible terrain (storm, or the other 4 team map with snow everywhere that is horrible for pvp, the mid at City, western with all those half slabs and fence posts everywhere and many more) and they all have random holes everywhere that make you drop into the void or make you get stuck or sometimes even block glitch.
In most maps the mids are so ridiculously tiny too, take Food for example, it is a 32 player map (quite big), yet the mid is puny, you can get shot off standing at the mid in like 3 shots. If 10 people come to mid at once (which is what usually happens since the map has many players) there's chaos everywhere since the mid is too small to occupy so many players.
Islands are also really close to all the other islands in most maps too, you can literally snipe anyone off a bridge from your own base in many cases that's how small the maps are. Now, people will argue "good! we can rush! games take too long!" well eggwars was never meant to be a rushing game, that's what speed eggwars/skywars is for. If you simply type "eggwars" on youtube the good videos are at least 20 minutes long, with the most popular videos being hour long epic intense games that require strategy and tactics. I understand that people want to rush people's eggs, but the maps should have islands further apart from each other so at least people have time to make sort of defence on their egg. An example of close islands is treehouse, you can literally tell your team to just bridge around the map breaking eggs and the whole map's eggs will be gone before 1 of them even has time to place the obby.
Another problem is players spawning a few blocks away from the egg. The prime example of this is on the map Space, where the egg is literally on the edge of the spaceship thing, and players spawn about 5 blocks away, and since its a map of 4, all of them can just keep respawning and keep hitting you off the edge. It would be better if players spawned quite far away from the egg to allow breathing space from when you've just killed a player to breaking their egg.
Anyway now onto teaparty and why it is the superior map. First of all the mid is well and truly great and magnificent, especially for a map of 40. In comparison, Mushrooms is also a 40 player map, but the mid is puny and there are measly bridges connecting everything so if a lot of people go to mid it is chaotic. In teaparty the mid is huge, with the right balance of obstacles to manoeuvrability, so fights are interesting but not stupid and annoying. There is a plentiful supply of iron, gold, diamonds instead of just 1 measly level 1 diamond gen at mid so you can get gear for yourself or get a good amount to upgrade the gens at your own base if you want to play safe. The islands are well spaced, you could rush another island if you wanted to, but it would give them enough time to put some sort of defence on their egg, and its also impossible to rush every single island which is good. It caters many playstyles. If you want to rush an island, you can. If you want to camp at your base and make a fortress and bowspam, you can. If you want to just TNT people to death, you can just trap people in those genius design of gen rooms at bases and TNT spam them (honestly, whoever designed those gen rooms should be given a knighthood). The egg is on the 2nd floor of the castle, people spawn on the 1st floor of the castle, so if you've just killed a team at the egg, you have enough time to break their egg before they come charging up with their wooden swords.
The islands are big enough to pvp on without having the fear of being bowspammed off all the time in a 1v5. Because of mid, camping teams are disadvantages because they have to share one diamond gen at their base, you can have up to 5 diamond gens at mid to yourself. Long, legendary games (the way eggwars should be played). My only problem with it is that in half health mode (why does this exist), if you fall to the bottom of mid from the table, you can die from just fall damage, but that is more of a problem with half health mode (seriously why does this exist) than the map itself. All in all a truly magnificent map that should be the inspiration of the build team if they want to make great maps.
11/10 IGN