User User Syncronization limitations on profile sharing

I am running a website where some of my subdomains require more detailed user profiles than others.

The master site requires only username and email, whereas one sub-site, running on the Jobroll theme, requires users to be identified as “recruiter,” “job seekers,” and etc.

One subsite running on the Directory Theme requires users to be identified as restaurant owners and etc.

Perhaps, I did something wrong, but when I made the master site share user data with the subsite running the Jobroller theme, the subsite crashed.

The front-end of the Jobroller subsite is no longer working, though somehow I can access to its Dashboard.

Can anyone suggest me how to cope with a situation where subsites require more detailed user profiles than others?

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