Well, Joric really didn't go up on the surface because he never had an opportunity - helping out his parents, training, as well as the concern that if he did go up, he would either find it to be an awful place, or find that it was a fantastic place and never want to go back home. He was around fifty when he finally left, which according to the wiki is the adult age for a dwarf, so he was still living with his parents as well.

And while that speech WOULD be funny, unfortunately it's not the kind of guy that Joric is (this isn't my first time using him in a roleplay, by the way. His last name would have been Ironfist, but apparently there's already a pre-existing clan of that name somewhere in the lore.) 

I'll bump it up to nine, because while he's not an eloquent speaker he isn't a complete idiot - just a bit below average, which was what I thought 7 was. I wonder how a level 1 intelligence character would sound?

Also his jokes don't usually have much thought put into them. He just says the first thing that comes to mind, and sometimes it just so happens to be clever.

Edit: I adjusted his stats accordingly, and mentioned the Silver Marches in his background. Still hadn't been to the surface before the collapse, but I added in the reasons why.

Edit2: You know what, I'll just swap his intelligence with his wisdom. He now has 12 intelligence and 9 wisdom.