Hi all,
Since the Goblin character alts are all stronger than the original characters they are modeled on, I developed and play with the following house rule in my Rise of the Runelords campaign:
No more than half of your party can consist of Goblin characters.
Feel free to try it out and let me know what you think! I think it makes the game more challenging and fun.
P.S. Incidentally, I think it works thematically too.....the relatively closed minded people of the Sword Coast don't trust parties of more than half Goblins to be their saviors....