If you spend any money at all for N3V DLC (Payware) then consider Gold as you get access to all Payware. My in game "Store" currently has about 60 routes to download and countless Loco's, trainsets, and rolling stock. (I have Gold.) You also get a nice store discount so, in theory, you could get Gold for about a month or two, buy what you want at discount, and then quit Gold. When you quit the subscription all the Payware content goes away but then you will have purchased outright what you really want at a nice discount. Obviously you keep what was purchased outright.
If you pay by yearly subscription it's about the cost of going thru the Drive Thru a couple of times a month. Much worth it to me. You learn much from all the varied routes. Some routes are old, but you can still learn a lot. Also, Tane sessions run better in Tane so it's nice to get a copy of Tane to use too. Tane sessions in TRS-19 tend to "break" - Signals stuck on Red, some crossing lights not working, etc. Better to run Tane sessions in Tane.
Hey, try it for a month just to check out all the content. I confess that I do have Gold/Plus primarily for the "Plus" feature though. I have several installs right now (see my signature.) I really look forward to getting the beta's and checking things out.
But having all the content is great too. If you install all the routes (I have a 2TB SSD just for content) then your chances of having "missing assets" when you download Freeware (DLS) is less. I have all routes installed in my "main" install. Beta installs have much less content but I can always check main install for any missing kuids for routes in those "lesser" installs.