I've been using Roon for about 8 years and bought the lifetime subscription after the first year. Besides the great user interface, what I like about Roon is the ability to use it with a wide range of devices without having to change anything in my library, playlists, etc. And the ability to play the same or different content on multiple devices at the same time.
I currently have nine endpoints connected to my Roon system - four Bluesound Node 2is, two RPi devices running Ropieee, an Auralic Vega G2, a Sonore Signature Rendu SE, and a Wiim Ultra. It's not unusual for me to be playing different content on 4-5 endpoints at the same time.
My library is a similar size as the OP's - slightly more artists and albums, slightly fewer tracks.
I started out running the Roon server on my Windows desktop, then built a dedicated NUC i7 running ROCK. About three years ago, I bought an SGC i9 server which runs their propriety Linux OS. I switched to this because I wanted to experiment with HQPlayer.
Overall, Roon has been very reliable. I have had some issues with my Sonore, but I think this is related to the optical Ethernet connection. All my other endpoints have been rock solid.
The only other issue I've had is with the iOS apps. They work great when first launched, but if the device goes into standby and closes the connection to the Roon server, it often doesn't seem to reconnect automatically. Closing the app and relaunching always fixes the problem. If I'm doing an extended listening session, I'll set the app to stay on which prevents it from disconnecting. Tho iphone app seems to work a bit better than the iPad app, but the iPad app has some more features and is a bit easier to use.
I have found that Roon has continued to improve since the Harmon acquisition. It has gotten a little snappier, and, if anything, sound quality has improved.
My network setup isn't particularly complicated. Most of my devices are hardwired to a switch connected to my router. I think a couple of my Nodes are running wireless, but everything else uses a wired connection.