I'm a Djangonaut whose also built an (extremely simple) app with RoR. I like them both. I'm more comfortable with Python, so I'm biased, but Rails is full of stuff that makes early prototyping fast, and lots of TDD goodness. I remember the first time I used Generate and it barfed out all these files, and I barfed rainbows in amazement.
I drink most days, maybe 2 beers, or split a bottle of wine with the SO. Some days I drink more, when out celebrating or after a really lousy day. I try not to get drunk, but it happens occasionally.
A user should never have to search a pdf for an error message. Nor should they every see an error of this complexity. And yes, the IRS should be able to programatically find your error and email you directions, written in simple english, on how to fix your submission.
Heroku makes it possible to scale fast. If you need more resources, just turn up the dials. But it can get expensive, so if and when you get high traffic, you should start looking at more customized solutions. Keep in mind that needing to refactor because of scale gets filed under "problems you want to have."
The answer depends on what your main project is. But getting free press from HuffPo, Yahoo, etc., is an opportunity few will ever have, so if the main project isn't something amazing or highly lucrative, I'd say it's time to pivot.
