The A10 chip might be the first time when the iPhone doesn't become dramatically faster year over year. Chip manufacturing has gotten better, so the iPhone 7 will probably get slightly better battery life and maybe run 10% faster, but it isn't going to be twice as fast as the 6S.
The iPad 4 came out to fix the iPad 3, which was incredibly slow when it launched, and very expensive to manufacture. There is no similar need now.
I think there is a 0% chance of a new 9.7 Pro this year, and maybe put it at 40/60 for whether there is a minor upgrade to the 12.9. I'm leaning towards no update (and possibly no A10X processor at all). But maybe they will replace the iPad Air 2 with an Air 3 running a non-X A10 processor. (that would make sense because it would be a lot cheaper to manufacture than the current Air 2, just like the chip in the iPad 4 was a lot cheaper to manufacture than the massive iPad 3 chip). The original iPad Air had a non-X A7 chip and got excellent battery life. Apple also released an update to the original iPad 2 that used a cheaper, more energy efficient processor and kept selling it for years. I think it is actually very likely that we will see them do that again this year with an Air 3 at the $400 price point.