I agree. Sara Rue's character and Leonard just don't work together. There's no connection (good OR bad), and I'm just not interested in their relationship at all.
Lorre apparently keeps trying to introduce a "second woman" into the formula, but for me it hasn't worked with Sara Rue OR Sara Gilbert.
At least not yet.
I say BRING BACK SHELDON'S TWIN SISTER and have her become best friends with Penny! Or even better, have her become the university BOSS of all four guys. Can you imagine Sheldon having to report to his sister?
--Ted