The use of notation software is acceptable. :)
Overall, I think notation software is good for concepting, but it's not going to take it to that next level of polish. A midi controller goes a really long ways in making humanized, realistic, expressive dynamics. It's very hard to artificially create the dynamics that come out of you when you're in the mode of experiencing the spirit of the music.
In fact, in a lot of my tracks, sometimes my first take is the best take, and I can't even recapture the magic of the first take, somehow.
So, imagine how hard it is to get that vibe check clicking dynamics in! I definitely recommend a midi controller to any aspiring composers - a weighted full keyboard is best and is what I use. It's not a super expensive top of the line one either - just enough to play notes and make music.
This is a nice composition, great work! :)