Can't go with you,,, but I will put a plug in for fishing out of Quepos on the central CR coast as compared to Guanacaste on the NW coast (where all the charters fly to the resorts). Feb / March traditionally sees calmer seas and a much hotter sailfish bite in Quepos. In addition to that, Quepos is a really neat fishing port / town with numerous options for accommodation ranging from inexpensive villas / posadas to boutique hotels and eco resorts. Nearby is Manio Antonio National park with one of the best beaches in Costa Rica.
I am sure you will have great time.