: right now each Google account can only have one identity. Maybe in the future it will be possible to connect your Google account with Google+ with the Google account you use for Google Play, but right now that's not an option.
The same is true with YouTube channels. Each channel can only be connected to a single Google+ Profile or Google+ Page. Google+ Pages each have their own special Google account, so it's still one YouTube channel per Google account. The difference is that Google+ Pages (and connected YouTube channels) can be managed by multiple Google+ Profiles.
I have multiple Google accounts myself, and I agree it can be a hassle to not have all options on all accounts.
I recommend that you provide feedback to Google+ directly, using the Feedback link at the bottom of the left menu. They do make note of feature requests.
yes, you are right, I was a volunteer in the G+ help forum)