Having just recently gone back and TT-ified a report generator (that in 20/20 hindsight probably should have started with a template :) I'd offer at least this advice:

If you do use here-docs and/or qq{} try and make as much effort as possible not to interleave any computation or manipulation in with the printing. That way in n months when you do break down and bite the bullet (because after the xth request to add just one more thing . . .; oh, and we want a Blackberry friendly version of the same information so you need to make another copy aimed at a 2" wide screeen but the BB browser is dane bramaged enough to not understand sufficient CSS to do it that way) you don't have to spend a bunch of time extracting that logic and moving it elsewhere.