At the moment, if an entity is used anywhere in LightSwitch, all of the properties of that entity are transferred from the datasource, regardless of whether they are actually displayed or used at all.

For example, if a choice list is displayed, showing just the textual summary property of an entity, if that entity has an Image or Binary property, that is also transferred in its entirety. This slows down the interface dramatically.
Even if Image or Binary properties are not used, on large entities with a number of properties, it is very inefficient to transfer the whole entity when only a single, or a handful of the properties are actually going to be used.

I propose LightSwitch decides which properties are going to be displayed, and does the equivalent of (for example):
SELECT id, name FROM entity
rather than
SELECT * FROM entity