I'm also planning a trip to Hawaii in 2013, August timeframe.
I'm planning to use two different airlines, Hawaiian Airlines and either Southwest or Jet Blue.
Southwest or Jet Blue will take me from east coast to west coast. You could do Southwest out of BWI.
Hawaiian Airlines goes to direct Maui from Seattle, Portland, San Diego and Las Vegas. HA goes from Los Angeles to Oahu, from there you hop to Maui.
With the Marriott travel package, you get a 7 day cert and your choice of 50k-70k-100k-120K miles. When you subtract the points for a 7day cert from the total, the MRP to HAmiles is 1:1. For example, 7days at a Cat 7 with 50K miles is 260K MRP. 7 nights at a Cat 7 hotel is 210 MRP, 35K*6(4nights, 5th free and 2 nights). 260-210=50.
Depending on when you book, HA coach seats are 20K-30K-40K miles and first class are 40K-60K-80K miles.
I haven't looked at other airlines to see if you can beat the 1:1 ratio.
Happy trails,
Henry