While I hate to mention the competition, there is one that is doing this and we found it beneficial. It's the notion of a data card or data set that can be related to the individual for keeping track of multiple items without creating multiple fields.
An example would be contract information - an individual may have multiple contracts each with unique identifier, expiration, etc. It would be nice to be able to associate this set of information to the user but not have to create fields for Contract 1, Expire Date 1, etc. that is visible at the root for all leads.
Another instance is promotions where they are responding and selecting a fulfillment item, would be nice to have this associated to the individual similar to contracts instead of endless fields on all leads. It simply scales in a different direction.