If you have good handwriting, then it is IMPOSSIBLE for you to be an aspie.
j/k
My handwriting is terrible. Growing up, my mom was convinced I couldn't read my own writing. Actually, I could make it out quite easily. If I force myself to slow down, I don't do so bad. Now I type almost exclusively. Sometimes if I'm brainstorming or writing down song lyrics or ideas, I'll use paper and pen/pencil simply because there's just something about that contact with paper, scratching things out, re-writing things, and so on that makes the creative process a little more "real." But once an idea has been developed, I immediately go to the computer and type it in Word or something.
I used to try writing music out by hand, also, and for most of my undergraduate college years, most of my music theory assignments and my first little compositions were all hand-written. But because of the difficulty of it, I started using music notation software as soon as I could get a working laptop I could afford. Now I'm NEVER without my laptop (MacBook Pro).
Very recently, like in the last month, I've returned to writing music the way I used to right before college: Recording the music first and transcribing it last. Ideas come too fast to be concerned about what kind of note comes here or what chord I want to play there, and that explains why so many years have been wasted with very little musical output. Having the best tools for the job is the single best way to get things done correctly and quickly, so now I'm working more in a workstation environment rather than staring at a blank screen all day.
Now, I know you aren't talking about writing music, just handwriting. The best thing I can think of if you need to organize ideas and write them down is figure out some way to dictate what you want to write on a voice recorder. Ideas seem to come as quickly as you can speak them. Writing from the get-go just takes too much time.