Platokidd,
Yes you have it all correct. Since you are in the US the Ecowitt GW1000 that you buy on Amazon.com (US Amazon) will be the correct one for the US using 915 MHz, and that matches your Ambient WS-2000.
Then yes to save technical setup know how (like flashing custom firmware and possibly needing to know how to use a TFTP server..etc) you can get the Ambient WeatherBridge. If you feel up to the DIY task then you can get a TP-Link TL-MR3020 ($25+shipping), and then add the Meteobridge software and license (65 Euros), and then optionally also buy the AmbientWeather.net license ($150) if you want that extra optional feature. Total price for Do-it-Yourself is $98 plus shipping with no AmbientWeather.net license or $248 plus shipping with optional AmbientWeather.net license. Which is why depending on if you do want the AmbientWeather.net license it is just cheaper to just get the Ambient WeatherBridge ($204) as it is all in there and preloaded and fully licensed for both Meteobridge software and AmbientWeather.net and it is has less technical know how required because you don't have to build it.
I've plugged in the GW1000 into my Meteobridge (Weatherbridge) USB port because it was convenient. All that does is give the GW1000 power. There is no data connection happening there. You could plug in the GW1000 to any other USB power source if that is more convenient for outdoor sensor array reception and if you wanted the Meteobridge at a different location for some reason. The Meteobridge by the way can connect to your network via WiFi or via Ethernet. You start off with an Ethernet connection just to first configure it and then you can switch to WiFi if you prefer that.
The GW1000 is essentially a second console for your weather station. Just like adding a second display console. You can have as many consoles as you want. The consoles don't know nor talk to each other, as they only see the sensors. The sensors don't really talk to the consoles either...they just send a radio broadcast signal that any console can pick up, so they too don't know if the console is listening. It isn't a two way communication. The GW1000 has its own built in barometric pressure sensor. Therefore yes, you would need to calibrate it. But it is really easy. Just enter into the configuration settings the same Absolute and Relative pressure numbers that are currently showing on your existing display console (provided you already calibrated your display console)
I still suggest you read the following regarding getting the Meteobridge and GW1000 to be properly calibrated.
https://www.wxforum.net/index.php?topic=36787.0By the way you do keep using your indoor barometric sensor that came with the WS-2000 so that you can continue to use that display.
* FYI - The Meteobridge (Weatherbridge) requires a 19 Euro update license every 2 years to continue to get the latest version of the software. But this is optional. After 2 years if you want to keep that last version you got, then that is your choice.