Just throwing this out there to maybe save someone else some pain for some items you might want to back up pre upgrade.
After upgrading to 7.5 a year ago and being in a world of hurt (missing images, DA broken), I didn't touch our CMS environment since in fear of breaking something else (and I was working with support on DA regularly).
I got everything working as I wanted to a week or so ago, so decided to upgrade now that SP1 has been out for awhile before 7.6 is released.
The upgrade process itself seemed to go OK. I contacted DS support pre upgrade who suggested I go to latest HF pre SP1, wait a day, upgrade to SP1, wait a day, then upgrade to latest SP1 HF. There were no errors during the upgrades themselves. However, in the console, every deploy task doesn't work anymore. Each deploy task produces an error in the console and in logs when I click on them, and all existing jobs using those tasks also don't load and produce errors in console.
Luckily, I can create new deploy tasks and jobs, but I'm not able to see the existing jobs to remember what XYZ software tasks were in the job. Support is working with me on that. Support asked if I had gone into my deploy jobs folder in console, right clicked, and done an export. I hadn't, but this may have saved me some pain to know the contents of the corrupted jobs, so I'll be doing that from now on pre upgrade, and you may want to as well. Support never saw my issue before though, so it's probably unlikely you'll see it.
Also, my custom sysprep files were deleted during the upgrade, I searched the whole server for *.xml. Luckily, with shadow copies, I got those back with some digging and have since backed them up elsewhere. If you use those, back those up too. I'm not sure if there's some 'safe' place they're supposed to be in the server, but apparently where I have them isn't it.
I also had some technician permission issues, but support quickly got that sorted out.
Here's to hoping that's all that's wrong in our environment, and I can get by not upgrading for another year.
One bright point, though, is I am very happy with the level of support I am getting now. I put a few tickets in and got a call back same day from US based techs who knew what they were doing. It seems the days of me getting overseas support who doesn't understand the basics of CMS/DS and me begging for escalation may be over - and I couldn't be happier about that. This great increase in level of support makes me so much more confident in the product whereas this time last year I was ready to jump ship. Thanks to the new management for implementing some positive change.