I understand what you are saying about Facebook app and its popularity. But in all fairness, SHOULD the onus be on Apple to make sure that everyone who develops apps is doing it 100% properly? Perhaps, as they offer them from the app store exclusively it's up to them to 100% vet them? I dunno. I guess I should read the entire 1.2 million page user agreement. It's probably in there somewhere... ;-)
All I am saying is that unless you have a hardware issue, I believe that if you go back to clean install - ie: setting your Pad up from scratch with 8.1.1 and no third party apps, it will be very close to iOS 7 in its operation. That has been my experience on several machines from this vintage.
Adding the apps back in can tell you when you experience system degradation.
Apple is not purposely trying to retire anything. When they don't want to support old product anymore, they simply don't support them. My iPod has not had an OS update since OS2 or whatever the last OS is that supported iPods. It was before iPhone, I know that.
So, end of life is not what is happening here. I really believe it is third party apps causing the problems. That is why the reactions to the upgrade are so drastically different. Indeed, they were drastically different on my very own iPad Mini. Once I found the Facebook App problem, things got better immediately.
For folks having issues, I suggest you go through the slog of reinstalling your system from scratch, through iTunes, setting your iPad up as a new device. Before you do that, back up to the cloud. Once you have it running as a new device, put it through its paces before you restore your data. See if it isn't working better. My experience says it will. Then restore your data, or add your apps one at a time from the app store to be REALLY safe. I am willing to bet you find it's a much better world on the other side. If not, you've lost an hour of your life or so - much less than the cumulative, frustrating time you'll spend trying to use it while it is crippled.
And again, sorry for sounding like a broken record. I write all this because I DID escalate it in The Lounge (where you have direct access to experts and posts get read by the hosts of this fine forum, but can't get there until you are level 6 at 8,000 points). It seems those with continued problems are definitely FAR in the minority. So, I am just trying to help. If you'd prefer I don't, just tell me and I'll shut up.
Thanks,
Bob