I'm so glad you switched to Electraks, Kam! These tyres
look big because their rubber occupies the space where normally the tread would be. Visual comparison of Electraks vs Schwalbe Marathon Winter Plus 700 x 50 makes the Schwalbes look skinny
You might be right saying there's still 3/4 inch left between the tyre and the fender; actual riding experience in the rain or mud can be shocking though. The volume left is so small that riding through the puddles makes rainwater leave the fender space so slowly you feel as if water were "boiling" there! With mud, it stays inside the fender. As I understand you live in South California and might never experience that. It is not
that dramatic (that's why I love Electraks) but Marathons Winter Plus leave so more volume between the tyre and the fender that riding in harsh winter condition makes snow (or rainwater) leave the fender space far easier.
Regarding the tyre pressure: The figures you have given sound right and allow soft riding. I typically apply 58 psi for both Electraks because I'm paranoiac about the rolling resistance
The chain: Isn't it you're riding with little motor assistance? It might explain the minimal chain wear. (I use a digital calliper to determine the chain wear; with the latest Shimano Ultegra XT CN-HG701-11-138, I was getting less wear than with previous chains).