Keep in mind Frontier also charges ridiculous 'close in ticketing' fees, so if you book less than 180 days out (I think, don't quote me on that number), you have to pay additional fees to book your award flight. They also tack on other stupid fees as well, like carry-on bags, checked bags, advance seat assignments, etc.

Seems like you're happy with frontier, but if I were in your position, I'd take a close look at Southwest's 50,000 mile offer instead.