D7 Profile Data Expandable by section

Looking for advice on possible modules or ways to accomplish an extendable profile with security at user and admin level for editing & displaying what is publicly displayed, restricted to specific roles / groups to view or which is user-only but which each person can refer to their own profile for relevant values they need from time to time. As time progresses more sections gets added to hold more data values, I envisage data would mainly consist of numbers or short strings of text not paragraphs of text but may be populated from drupal data like og groups

The aim is to provide a 1 stop location to hold data relevant for a user and also about that user which they can choose to publish for others to view or not. The quantity of fields and data types stored would have be flexible to accomodate different users and groupings of users. Data must be able to be updated by syncing to external sources like ldap directories where necessary. I would like if the data could be referenced in other drupal nodes to personalise content and as new required fields are added users have to supply a value or at at least reminded to fill it in on their next visit

Possible Modules
User relationship
Profiles2

Example Use: Conference is on in a secured venue where everyone needs to enter via keypad and unique pin. Site admin enables a new profile section "Conference 2012" for those attending with a field containing their pin. Users can find it under "my profile" page but also a help document node on how to access it personalised so its shown in-situ as well if an attendee should visit the page. Staff working in "Conference 2012" would also see a field for them with ia value of the web url to use to claim their hours and again a help document node could reference that data field to personalise a document explaining how actually to submit a claim. When Conference 2013 comes around a new section can be added to hold new data fields.

If data is changed notifications can be triggered to alert users to this. e.g. Site Admin changes web url to register for Conference 2013 all users are notified that their profile field changed.