When it comes to shortened words used for e-communications, vanity plates, what have you, we lean strongly (strngly) toward consonants. I've noticed that often enough to wonder what some words would look like if we used vowels instead.
Take the title of this post. Seriously would become something like "eiouy". Hard to figure out, hard to pronounce. Thanks--commonly reduced to thx--would be simply "a". Our language leaves no choice but to use consonants.