I have switched to the portable version of Miktex. All that is required to run everything is to add the Miktex path (say C:\Miktex\install\miktex\bin) to the existing path variable.
I previously used the installed version like you, but I now prefer this system because it can be easily backed up and transferred to another computer or just run off a USB drive.
If you switch to the portable version, you can transfer the existing packages that you already have installed across to the portable version using the commands (put them in a batch file to make it easy)
mpm --verbose --repository="c:\currentmiktex" --import-all
initexmf --mkmaps
initexmf -u
where, for example, c:\currentmiktex is the directory of the installer version of Miktex.
Update:
Here is an example. I deliberately deleted the storebox package from my portable Miktex installation on the c: drive. My backup copy on the USB i: drive still has this package, so that is the only difference between the two installations. When I run the batch file, it gets storebox from the i: drive (see picture).

My path variable includes c:\miktex\install\miktex\bin where all the Miktex executables live (this is permanently set up before calling the batch file). The repository should point to where the other Miktex files are (in my case the portable backup i:\miktex\install). See the picture for some of the directories under this directory.

I hope this helps.