One of my characters has about 6 with no shouts to spend it on since she doesn't go dungeon delving much. I reckon something that would be good is just a 'full restore' sort of thing - full refill of health, magicka and stamina and reduce any outstanding cooldown on shouts by about 120 seconds - enough to cool the more basic shouts like Unrelenting Force, Fire Breath and Elemental Fury but not too much as to cool advanced shouts like Ice Form, Call Dragon and Storm Call.
Ha! yeah, I actually got 10 right now. In the beginning I had more unlocked words without souls. Now it's quite the opposite. I find that I'll unlock a shout that doesn't even agree with me. I just do it cause I have a plethra of souls. That's alright. It's a good thing. I just need to find more walls.
I looked yesturday just to see how many I had. I was thinking maybe 4-5 and it was 10!! Dragons always seem to come up when I'm in a groove, then I'll fast travel somewhere and bam, a dragon's in the sky. Can be a little pest sometimes.