My current ratio is 3.305 (U: 7284.51 GB, D: 2203.83 GB)
Please be aware, there's a LOT of people with significantly more data transferred and better ratios, many of whom (like me) also don't mess with seedboxes. I use myself as an example, because I consider my stats to be relatively "middle of the road" for BakaBT (not that I've ever actually verified that - lol). I also do so, exactly because I don't use seedboxes or download a single thing I don't actually want; I take no "special measures" at all, beyond constantly seeding (no exaggeration; I leave my PC on pretty much 24/7/365.25). Additionally, I've been a member for
years; since the BoxTorrents days, in fact.
As for my connection, I have a very average cable connection for the US, 25-30 Mbit down (3+ Mbyte/s) and 4-5 Mbit up (500-650 Kbyte/s); it varies a lot by time of day). My current ISP is Antietam Cable, but I got almost exactly the same speeds under Comcast. Antietam, though, happily does not have any kind of bandwidth cap, unlike Comcast

, although the vast majority of my traffic historically was over Comcast. The same speeds, roughly, seem to have become a de facto standard over much of the Eastern US; I got exactly the same stats via Comcast in Ranson, WV as I did in Frederick, MD.
Sorry if my previous post was taken as bragging; I merely want to point out that it's possible to maintain a good ratio with almost ANY connection.