InfoPath Dev

I have an InfoPath 2007 Form that is backended by a SharePoint 2010 Document Library.  The app has been in production for several years and been updated dozens of times without issue.  The form has 400+ fields that were promoted into SharePoint "single line of text" columns.  I am testing the app in SharePoint 2010 and when I add a workflow to the Document Library I get:

The column cannot be added because the total size of the columns in this list exceeds the limit. Please delete some other columns first.

I have added new fields and successfully promoted them to SharePoint Columns many times in the past.

I appears in 2007 the column limit for Document Libraries was 2,000.  For 2010, it appears to be 276.  I have tried to increase the webapp's MaxListItemRowStorage but it doesn't help. 

Any words of wisdom out there?  If I move the backend from SharePoint to SQL server what might I use to replace SharePoint's View functionality.

:(

Wow - at first I was thinking that 2,000 must be a typo.... but it looks like it isn't & that the restrictions weren't based on column types in 2007 (per http://technet.microsoft.com/en-us/library/cc262787(v=office.12).aspx) and in 2010, they are. Are the data types correct on all of these? That is, they are all single lines of text? Or could any of them be modified to a different data type?