You should bump up those limits. Liability coverage is cheap and will keep you out of bankruptcy court if things go wrong one day. I have the max, $500,000 combined single limit, with another $1,000,000 of umbrella coverage hanging over that.
I'm dinged on a few areas I have little control over. First being the car, apparently it's one of the most popular stolen cars in America. Then our geography, we're in a part of New York with high DWI rates. Progressive was far and away the cheapest for both of us. I periodically check to see if this is still the case (easy to do when you work for an insurance agency) and so far it is. More's the pity.