Upgrade to 5.1 Questions/Issues

I upgraded a project to 5.1.  Everything seems to be working, except for a few things.

1.  I had a SearchBox control added to my masterpage and after the upgrade, it started throwing an error that the <sitefinity:SearchBox> control could not be found.  It appears to me that the SearchBox control was moved to a new assembly, so I had to change the declaration in the master page to:

I also noticed that in the predefined widget template for the search results widget, the "Titles" only widget isn't updated to have the correct declaration.  I started a new project from scratch and confirmed that the widget template is not updated.  I updated the template manully, but restoring it to default makes it wrong again.

2.  Related to the above, I had to add a reference to my project for the new Telerik.Sitefinity.Search assemblies to get it all working.  Should these assemblies be referenced during the upgrade?  I compared a new project to my upgraded project and found a whole bunch of assemblies that are referenced in a new project that are NOT referenced in my upgraded project.  This included all the MVC assemblies, the Telerik.Sitefinity.Services.Documents assemblies, etc.  Should we add everything that is missing  in as references?  Everything seemed to be working, but I thought it was odd that something was missing.  I'd like my project to be fully upgraded and close to a new 5.1 project so nothing is missing.

3.  When I go to the new Modules section under Administration, the "Search and Indexing" was not initially working.  It is working now, I think I had to deactivate and activate it, potentially after adding the missing references in the project.  The "Migration" module is throwing an error.  I don't think I need this, but thought it was odd.  I tried reinstallin it, activating, etc.  but it always shows "Membership provider with key 'OpenAccessMembership37Provider' cannot be added for module 'Migration', because a key with the same name is already added".  I thought I would just deactivate it, but that doesn't seem to work, it always has this error.

This is really the first time I have upgrade a production project, so running into some of these things is making me wonder if there is anything else I might be missing that I should consider manually doing to my project after the automated upgrade is complete?

Thanks,
Chris