I don't think Spike was particularly dumb or crude, as he could talk his way out of situations at least somewhat, making me think he had decent social skills, like Bluff and Sense Motive. Probably not the sharpest tool on the Bebop but definitely not brain dead. I'd leave his Int and Cha at 10. He's definitely Dex and Wis focused but he doesn't have any significant weaknesses, either.
I'd raise Wis to get more out of Flowing Dodge and to his AC in general. I'd also get Monk up to 5 for Elusive target.