[IE11 opens "meet your browser" on each start.]

Have you tried using SetupComplete.cmd to install IE11 and related updates?  That what I do and the "meet your browser" pages only shows during the first run.

[Create a batch file to install multiple *.msu files in running system]

A quick google search for "batch install msu files" brings up several threads from different forums discussing how to do this, so it is possible.  The person in the thread Kelsenellenelvian linked to was trying to use dism to do the install, which can't be done without extracting the cab file from the msu.

[integrating 2 updates in win7 x86 error]

I was having the same problem with the x64 version. After reading the KB article, under prerequisites I noticed this:

 

 

Additionally, you must install the following software:

• Microsoft .NET Framework 4 must be installed before you install Windows Management Framework 3.0.

 

After making sure .NET 4.5 got installed before this update, I had no problems with a test install to a VM.