I think you should put up any degree or cert. that inspires confidence in your client.
I would think most of them would like to see your UG degree, law degree, bar licenses for sure.
If you're in a financial sector of law, your CPA license could also inspire confidence that you know what you're doing.
Based on what I've seen in attorney's offices that I've worked for:
Other relevant professional licenses or degrees would also make sense to me. An M.D. or a Ph.D would sure look impressive to most clients. They look impressive to me when I'm in the offices of attorneys with them. Even an LL.M or an MA, or an MBA seems impressive to me. I knew a guy with a post-graduate certificate in "Domestic Violence Prevention" from UMass Lowell. He was a Family Law guy, so it made sense to have up. If he had been a personal injury guy, it would have seemed a little off to me.
I think that anything that makes an attorney look "smart" and that is relevant to the field of law is good.
A Notary Public license.... ehhh probably not so much (unless you're also providing notary services out of your office, I suppose.)
A paralegal certificate from before you were an attorney could be nice while you're a new attorney since you could arguable "tack on" that experience to your lawyering career... but once you've passed the "newbie" stage, I don't think it would be beneficial, and might go from "tack on" to "tacky".