Anyone can just throw everything they need within a portal. Adding a new field? Just throw it in the portal. But WAIT! The question is "Should you?". The fine art of determining what should end up in your portal is based on how the data and/or actions are being referenced/used.
Is the frequency for editing the data high or low? If it's low, then maybe the user doesn't need field access. What is the frequency of record deletion? Low? Then, do you really need that obvious red trash can icon on every row? How about supporting common keyboard navigation such as using up and down arrows?
These are the types of things you'll find addressed within this video. A lot of really nice tidbits of inside information with regards to working with portals.
Click the title or link to this article to view the video.