Have been lucky enough to fly to Hawaii the past 4 trips on FF miles from different credit cards. We have the United CC - when both my husband & I signed up - there was a promotion going with 50,000 miles - no annual fee and miles posted after first purchase (not after $1000.00 or $1,500.00 within 3 months out now). We had the Hawaiian airlines card from BOA until Barleys took over in April. Get for inter-island airfare but there is a direct flight from JFK to HNL. You just need to get to JFK. American Airlines Advantage card is not bad either. I would check out the credit cards for the below airlines. I know we constantly get promotions in the mail that differ from what is on the website.
Delta (not so easy to get FF seats)
United (have found pretty easy to find FF seats - also, can book one way FF seats)
American (have found easy to get FF seats - believe you can also book one way FF seats)
Just recently got the Alaska airlines credit card. 25.000 points after first purchase but most people get it because every year you receive a $99.00 companion fare with one full price ticket. Alaska does fly out of Boston.