Dunno why people think tank town was never used, actually the day I quit playing it was alive and well. People figured out that 135 was camped, so off to tank town everyone went. Three times it was packed during peak hours, at least before I quit playing - 135 was dead except for a few scavengers who thought they could break through 135.
Quite a few good battles took place there, then again a year ago is a different story, Don't know when Trinity was taken out or when it died, it was alive and well for me.
I actually liked the Tank town area on trinity, it was well mapped out with tons of space, unlike the Islands map where you basically have three giant mountains that you can't exactly drive around, so you are in a limited area. Trinity allowed people to flank and it was pretty fun watching Tiger2's pop out and get sniped by M18s.
Unfortunately It wasn't always busy, but then again I don't know how the numbers have been from 2 years ago till today.