Take heart Alex, your concern with the new iOS7 is appropriate. It is your machine, after all. For someone so "old" you are pretty up to date with your hardware. I have a third generation iPad. I also have an older version of the iPad2 and the very first iPad. I'm going to get the new iPad Air, eventually. To me, that is where the issues lie, in hardware--software is easier to fix.
My team supports our end user's iPads and we have advised them not to upgrade to the new system because we have company specific apps developed for company owned iPads. However we have also encouraged employees to upgrade their personal iPads to the new version, at home, over the air or attached to their home computer via iTunes. We have asked them to let us know if they noticed any thing out of kilter technically.
iOS7 does provide a totally new user interface, it does have the look of being re-designed from the ground up. With anything new and different it does take time getting used to the new system. For example, if you wanted to look for something on your iPad, you can go to the first screen on your home page and search there. The new interface requires you to run your finger down on your home screen to recall the search function. Another example, in the past double pressing the home button reveals your task bar of recently used and running apps. You had to press down on an app and then press the x to remove it from memory. In the new interface, if you double tap, you get a smaller version of the app and to close it or remove it from memory, you simply swipe up on the app.
I am using these two examples because these simplified functions impact my company's apps designed to make finding stuff and closing apps easier for our end user. So we are either going to have to re-write these apps, or train everyone how to use the new gestures. Believe it or not, it takes a lot of time and money to develop an app--about as much time and effort to train people. But which has greater value long term?