Even with all those question marks on the roster at the end of last season’s surprising run to the second round of the playoffs, the Islanders managed to remain almost an identical team.

The club was able to re-sign three of their four big pending free agents, locking up captain Anders Lee, along with forwards Jordan Eberle and Brock Nelson. The one who got away was goalie Robin Lehner, a Vezina Trophy finalist who turned his personal and professional life around and then was oddly pushed out the door with an ultimatum laid out by team president Lou Lamoriello.

And yet as coach Barry Trotz enters his second year, a lot still needs to be figured out by opening night.

1) Will Trotz’s defensive system wear thin?

A year ago, it was easy for the team to listen to a new coach who had won a Stanley Cup just months before. The team went from last in the league in goals-against to first. But after all of their individual offensive numbers went down, do they continue to buy in with the same vigor?

2) Who’s the starting goalie?

Lamoriello replaced Lehner by signing Semyon Varlamov to a bloated four-year, $20 million deal. The 31-year-old is coming off one of his worst seasons, but the hope is that he is here to mentor fellow Russian Ilya Sorokin, if Sorokin finally comes over from the KHL next season. With Thomas Greiss still having one more year left on his deal, time could be split.

3) Will Nick Leddy be on the opening night roster?

With the club having a handful of young defensemen in the pipeline, it seems like Leddy is the most attractive and expendable trade piece the Isles have to add high-end talent up-front. At 28 years old, Leddy has three more years left on his deal, with a relatively modest annual cap hit of $5.5 million.

4) Will Josh Ho-Sang finally grow up?

The terrifically talented winger (and interesting person) has been through so many ups and downs, but his lack of maturity has kept him from sticking in the NHL. Having signed his qualifying offer as a restricted free agent — one year, $874,125 — this might be the 23-year-old’s last chance with the Isles.

5) How will young and old mix?

Lamoriello signed former Rangers center Derick Brassard to a one-year, $1.2 million deal, adding him to a stack of veterans up-front. There are high hopes in forward prospects Oliver Wahlstrom, Kieffer Bellows, and Otto Koivula — along with defensemen Noah Dobson, Bode Wilde and Sebastian Aho — so who will make the team and where will they fit?