I'm not adverse to a large phone, but if the leaks are a fair representation of any Nexus 6, what's putting me off is the look - like the Moto X 2014, it's just a phone - it's a step back 5+ years. I'm generally not one to buy devices based on looks, but I'd like something where some thought has gone into the aesthetics of a £300+ device.
The Nexus 5 looks fairly plain, but in an understated, sleek way. This isn't even trying - it's just there. Hopefully the shell is just a placeholder.