External List in SharePoint Limitations

When I tried to connect the external DB to the SharePoint using external content types, I found lot of issues or limitations for the end users. This is same in external lists as well. I am using SharePoint 2010.

No look up:

Unfortunately the only thing that you can do a look up on in an external list is on the ID column, anything else and you are out of luck.

No Attachments:

Attachments options are not available.

No RSS Feeds:

RSS feeds is also greyed out and it really helps when you need updates from SharePoint list

No Workflows:

Workflows are very important in SharePoint lists and it plays a vital role in different business requirements. But workflows are disabled in external lists

No Ratings:

In all the SharePoint lists, you will see an option of Rating Settings under General Settings where the Rating can be enabled but this is disabled
No Inline Editing or Datasheet View:
Inline editing allows you to edit list items in list view itself. Datasheet view is a where you can easily change the data for multiple items. Neither of these is available.

No Versioning or history:
You cannot see version history for an External List. It does make sense, in many of the external systems there is no concepts of version
No Item Level Permissions:
You cannot configure item level permissions for external list items
No Export to Excel Option:
This is a frequently used option which allows the end users to export the list data to excel. But this is disabled
No Open with Access / Create Visio Diagram / Open Schedule: 
Though this not used frequently, sometimes we may need this but this is also disabled

I gone through BCS in SP 2013, it is improved a little bit:

1. Export to Excel option is included
2. Sorting and Filtering are improved
3. Event receiver on external lists is introduced