As Microsoft determined LightSwitch as tool not only for developers, it would be very useful to have Report Designer and be able to make Report directly from LightSwitch.
This is one of the most wanted feature that non-evelopers need.

At the moment, making reports is bit of challenging and need a big efforts to be done.

First, congratulations for this product, its an old wish i had. For the completness of this tool, i think its fundamental to have Lists and Datagrid conditional formatting.

In a real world LOB system, there may be a lot of menu items, which should be organized in a hierachical navigation menu.

The ability to developed LS applications in modules. Most LOB applications start off simple and evolve over time into large systems. The ability to develop smaller modules and link them together would be a great advantage in LS.

Display of hierarchical data is a requirement in many business applications. The forums and blogs are full of questions on how to add a treeview to a Lightswitch application. While it can be done with a custom control, adding it to the standard set of controls would certainly make Lightswitch a more powerful business application development environment. BTW, be sure and have a two-way SelectedItem property.

If LightSwitch will easily support update, insert and delete stored procedures it will allow my company to adopt LightSwitch. We cannot build a separate WPF project each time we want to modify the data this way--and from inside LightSwitch it is just too slow and too complex to do. Thank you!

Often I'm finding screens may have similar custom layouts, but I need to build each one from scratch. I have to flip back and forth between screens (see my other sugg. "Allow developer to have multiple screen designers open simultaneously."), and manually tweak the hierarchy to get screens to be consistent with each other. I'd like to be able to select a node in one design screen, copy it, and paste it into another.

Today it is a lot of manually coding to build a application with a many-to-many relation.
It would be nice to have more out of the box support for this.

Exporting to Excel is only available for local desktop applicaitons, but more applications these days are deployed as web applications. The export to Excel feature is incredibly valuable, and would be a great addition to applications deployed to the Web and Cloud.

It would be great to be able to use any standard Silverlight control in LS without having to create a "custom" control wrapper around it

LightSwitch is currently limited to run on .NET 4.0

.Net 4.5 have great new features, when will LightSwitch developers be able to take advantage of these new features? List of new features here:
http://msdn.microsoft.com/en-us/library/ms171868.aspx

Our server is in our control and we are not limited to .NET 4.0, but if other users where limited to .NET 4.0 it would be much better if Lightswitch (like other Visual Studio projects) supports more than one target version of .NET Framework for it's server code. This fact has already been determined on these threads:
http://social.msdn.microsoft.com/Forums/en-US/lightswitch/thread/081faa3e-a2fa-4e79-8720-a5ac2096e764
http://social.msdn.microsoft.com/Forums/en-US/lightswitch/thread/11849e56-e9cf-4813-8f7f-80aa63a53837/

ability to create a metro app (arm or x86) including metro UI elements in LightSwitch

I would like the ability to specify an icon for each menu item and to set a default icon for all menu items.

I was looking at my LightSwitch applications, wondering why they didn't look as good as the Windows Azure Dashboard. The basic layout of both is very similar, but I think one of the major differences is the ability to include images beside each menu item. The Azure dashboard includes many images, even if they are only simple folder icons. An icon beside the menu item would go a long way toward a more professional looking app.

Make Table inheritance. So developer could make some BaseTable (entity) and a number DerivedTables (entities) witch will inherit properties from base table. And also it would be great to mix properties from base and/or derived tables in queries.

Hability to serve multiple databases with the same deployed instance

Enable the ability to easily change the connection string in the designer. A server name may be changed, or the database may be relocated. Currently, every screen would need to be recreated to accomplish this.

I believe it will be very useful to have a "Preview" Tab while desiging LightSwitch Screens

Suggested Preview Modes:
*A Full Preview for the whole Screen
*A Partial Preview to see group/s (control tree)

Imagine a system has 100+ tables and screens, without the folder, it's too hard to find which table/screen is in which domain.

It would be great if there was official support for Microsoft-Sync (or similar technology) so field devices (or laptops without internet access) could use LightSwitch apps offline and sync once they were back online.