The New York State Legislature will be up for reelection as well in 2018.
The New York State Senate, which has been changing Senate control in Albany for years is currently held slightly by
N.Y. Republicans due to the Independent Democratic Conference's breakaway eight members including State Senator Jeffrey Klein (D-Bronx/Westchester). Klein is facing accusations of sexual misconduct.
https://en.wikipedia.org/wiki/Independent_Democratic_ConferenceKey Senate seats to watch IMO:
Marcellino (NY-SD-05)
Hannon (NY-SD-06)Brooks (NY-SD-08)Klein (NY-SD-34-IDC)Golden (NY-SD-22)Avella (NY-SD-11-IDC) https://ballotpedia.org/New_York_State_Senate_elections,_2018For the New York Assembly,
N.Y. Democrats have controlled the Assembly for decades and are heavily favored to do so again, with most New York City-centric members being reelected to safe Democratic districts.
https://ballotpedia.org/New_York_State_Assembly_elections,_2018