Ironically Frontier was the 2nd card I applied for since they fly local out of Trenton for me. What a miscalculation, the Trenton flights that I was interested in, were all basically Tues/Thursday and it was nearly impossible to fit them into my schedule.
After holding out hope for about 2 years I finally converted them to Radisson hotel nights, found on their partners page.
They emailed me vouchers of 25,000 points each night and I called and booked the hotel myself, A redemption rate of about .008 for $200 night room. Not the best but better than letting them sit and rot