Yeah, if you enjoyed N+ you're going to love N++, the graphics are nice, great music, tons of colourschemes, lots of features like level creation / sharing, online scoreboard and replays with optional uploads: you can see how other players completed levels. There's local co-op and versus, also works online via Steam Remote Play Together or Parsec. Highly recommended.

Just be warned that sometimes save files can get corrupted and wipe progress, the most popular guide is a warning for this and instructions for backing up your save. I had it wiped once a few years ago and I've been backing it up since, it's not super common, devs have looked into it extensively and are stumped.