Modify username + jomsocial

Question

I've used Jomsocial plugin in my site.

And I found that there are only 2 options which are Real Name and Username for displaying on front page.

I am wondering how can I customize it so that I can make it display in another format.

For example, I want it display

• user's first name + City
• Or user's first name + last name's first letter(Tom G/Tom.G)
• or may be I can show a custom field like "display name" that I've asked user to fill on registration form.

Thanks!