Personally I use public trackers the most and only recently private trackers for stuff in my native language.
I did setup i2p a few days ago and currently have only downloaded around ~1GB. Most of my bandwith (143 GB in / 135.5 GB out) has come from just having it in the background 24/7.
The advantages of usenet don’t really apply to me (longer retention, faster speeds, no vpn)
Streaming i find useful for checking if something is worth downloading
Digitalcore is currently open (.club) scenetime was open aswell recently
They are fine for the beginning. morethentv for tv, nebulance for tv
Private-hd for tv and movies in … hd
Torrent leech for everything scene
Usually having one decent profile (ratio) helps you to get into other trackers