The Islanders met together at Nassau Coliseum yesterday for the last time this season and spoke optimistically of a bright future, full of playoff berths and runs at Stanley Cup titles. But now, the real questions begin. And they revolve around three key veterans — goaltender Evgeni Nabokov, top defenseman and captain Mark Streit and first-line forward Brad Boyes — who made the Isles’ first trip to the postseason in six seasons possible. “I hope we’ll see all those guys back,” said star center John Tavares, one of three finalists for the Hart Trophy. “The leadership they brought [meant] leaps and bounds for us getting over the hump in a lot of ways.” The trio are all unrestricted free agents. All three expressed hope of coming back and building on this year’s success, the late-season run to the playoffs and the dogged fight in the opening-round series loss to the loaded Penguins in six games. But nothing is a given. Head coach Jack Capuano declined to address their status, deferring questions to general manager Garth Snow, who didn’t speak to the media. Capuano did praise Nabokov, despite his uneven series against Pittsburgh in which he allowed 24 goals and compiled a soft 4.44 goals-against-average and pedestrian .842 saves percentage. “I don’t think Nabby had a chance on a few of those goals,” Capuano said. “He got us there, he played a lot of hockey, and I thought he did a real good job for us. My mindset doesn’t change on Nabokov.” Nabokov, 37, said his agent spoke to Snow four weeks ago, but they haven’t talked since. There were contract negotiations early in the season, but they broke off. Nabokov expressed interest in his exit meeting of coming back, after a rock-solid regular season in which he had a 2.50 GAA and .910 save percentage.