So I got a new lens

I figured that 80% of my shots were taken with my kit lens (the others being sports with my telephoto) The 17-55mm was just way too expensive, so I've settled for a sigma that was half the price.
These are some shots with my new Sigma 18-50mm f/2.8!
Even weeds can look good 
http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4026.jpg
I like the colours in this onehttp://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4080.jpg
http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4074.jpg
http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4063.jpg
http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4066.jpg
http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4067.jpg
Now a few non-flower pictures:http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4243.jpg
Might have over-prossesed this onehttp://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4196.jpg
"Guitar Hero" controller:http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_1710.jpg
And my little doggy
he loves to eat grass!http://i652.photobucket.com/albums/uu242/Justin_Cambridge/IMG_4057.jpg
My next piece of equipment will either be a good flash, or a 85mm f/1.8. I want a fast prime that will be able to take portraits and maybe pictures of basketball from the sidelines - is 85 too short/long for that?
any suggestions on which one should be my next purchase?