Samus' controls are improved from the first game and a number of series mainstays would make their first appearances here (this game is not given the credit it deserves by Metroid fans)
Biggest problem is the lack of visual variety which can make backtracking confusing. I played it with only the official GBC palette for authenticity, but there's a colorization romhack out there that looks good and gives it different color palettes for different areas. Highly recommended, in hindsight I wish I used it.