By over lining... You mean go up a line size.. I does feel stiff..
Yes, going up one weight on the line will make the rod bend a little deeper giving you more leeway in your timing. As someone else noted there are lines made a half-weight heavy as they come. I am not a fan of them in general. If you need the extra weight you need the extra weight and a half step is not usually enough for short casting improvements.
Obviously, the more line you have in the air the more it will weigh, and quickly...
