Using Waterfall Velocity, a Minecraft server proxy, you only need one address to be able to connect to multiple servers.
Using the new configuration I have combined all servers under one address and port so there is no need to have multiple TNTable servers in your list. I discuss the specifics later. For now I will just give you the commands to get around. They are also really easy to find on the server. At any time start typing "/server" and a list of autocomplete suggestions will come up with the available servers.
/server SMP
/server UHC
/server Creative
Waterfall is a fork on BungeeCord, a Minecraft server proxy. It takes BungeeCord and optimizes it further.
!! Waterfall is no longer being used, Velocity has replaced it. It provides the the same functionality with additional performance improvements. !!
A server proxy allows the addresses to be combined into one so that multiple servers are not needed in the list with multiple ports or extra configuration at a DNS level. Waterfall is advantageous for me as I can create additional servers and configure waterfall instead of worrying about additional ports needing to be opened and all the extra configuration that would otherwise be required. Travelling between servers is easy and it will remember which server you were in before logging out and place you back in there when rejoining.
The server address can be found in the TNTable Discord community. Ensure that you have given me your username before joining so that I may add your name to the whitelist. By default you will land in the SMP server but switching is a command away.