From your complaints about the Tarmac, I'd conclude that any Felt F-series bike would not resolve your issues. I love Felts, but the Fs have a seriously low head tube (lower than your Tarmac) and a longish top tube. That equals aggressive riding position.

Hey, the Z-series is made for guys like you, guys who'd be on a Roubaix but are too pissed at the Specialized dealer to go back.