I have had the this setup since 1993. Before that I and a Davis WMII. I have a VP2 Plus, two anemometers with one to a wire anemometer transmitter. That is in case one of the units isn't working, such as due to critter or freezing rain. When I set up the mast I was younger. Now that mast isn't coming down in case the top unit craps out.
I have a FARS kit as well. Then there is the soil moisture unit.. I have with that a completely populated soil/moisture station at 4, 12, 24 and 36 inch depth. Also a leaf wetness sensor. When my ISS needed a new super cap, my arm was in a cast, so I purchased a new board and with the old waited until I healed and replaced the super caps and decided that I could use a soil temp. sensor for surface temperatures, and I had a spare solar panel unit. So that is there.
I also have a Bloomsky2 camera out there, in the family room window, I have a Foscam R2 camera for the South sky, and another peeking out the front window at the North sky.
Oh I have a temp humidity sensor in the attic and one in the basement and yet another in the crawl space. I am almost fully populated. I have one transciever spot open.
I have one console in the kitchen, another by my iMac that has an ip logger, Two Envoys one with a IP logger for the Weatherlink 2.0 site and the other for my website . The other is a USB that I use with Weathercat and Weatherdisplay . It is my website backup, so if the IP loggers crap out, I can go natural.
One rule I have always reminded people of, where ever you happen to put your weather station, remember you have to do maintenance on it. If you put things on the roof be sure you can get up there in various weather conditions without bouncing off the roof and amazing your neighbors.