The one thing about reconfiguring a computer is the time factor - it just takes so much time to back up, reinstall and then reload. You can only go as fast as your computer allows, and sometimes even slower than that to make sure that the machine and software both cope with the changes. Past experience has taught me that the OS does better if you give it time to think between all that loading of programs and files.
My clean install project has gone relatively well, and now I'm reinstalling backed-up documents. Tomorrow I'll start on the programs. I have decided that I will make a snapshot image of the hard drive when all the programs and files have loaded. That way, when I next need to go through this torture, I can simply load the image onto the formatted hard drive, saving a whole bunch of time.
Something I haven't done before is reinstall Adobe Lightroom. Lightroom acts like a data base. It doesn't store photos, it captures information on all of your images, including any post processing that you have done in Lightroom. The data base is backed up, but I am nervously waiting to see whether the program is just as it was before I reformatted. I am at least expecting to find that the program has lost its link to each image, but I am also hoping that I am wrong on that count, as that outcome means a whole new bunch of required time.