I'm not sure what upgrades I could buy for the cost of a $4 can of spray paint.
If all you're going to do is spray paint it, I would paint the seat post clamp, headset and/or spacers, maybe the rear hub the same color orange. Then you have a well "flared" bike. You can trick out any bike with a lil spice tastefully. I'd rather compliment a bike with combo colors than all the same.