You mentioned that you used Logic, a program that I know little about. I use Reason, an equally pretentiously named program that's 100 times less learner friendly than the name would suggest. I'm going to program a DAW called "Common Sense" and the learning curve will be so steep kids will literally get hurt trying to climb over it.
"Picking out instruments." It's always good when a sound bank has what your looking for but I might suggest toying with initial patches or resting devices so that you can synthesize your own instruments for a second? Presets aren't dirty or anything but learning to make your own synths is like learning to make your own food. You will never go hungry ;)
Like I said, Logic is not my baby but this little tutorial video looked like a solid bread winner.
If newgrounds adds a space in the html you'll have to delete it.
The arps in the second half of the song were pretty! What did you use to write them? Pure curiosity. Was it the preset instrument? Most DAWs have an arp effect or device of some kind that you can plug into most things. Usually. I'm not fact checking that but it's true. Arps are a totally legit way to compose. Just... don't let anyone know you do. Shhhh. Arps are the sexiest way to make chip tune synths from squarewave and sawtooth oscillators. Don't. Tell. Anyone.
Ahem. You have a knack for arranging musics together! Hope you hang out a while and keep composing :)