I would buy the 10.9 in a heartbeat.
I use the iPad at work intensely throughout the day. I've longed for a size between the two Pro models. The 12.9 is just too big and bulky, the 9.7 is perfect to carry and not be obtrusive or rude in meetings. But the 9.7 could use a bit more screen real estate. A 10.9 in the package size of a 9.7 would be heaven. Happy to pay a premium for it.
Of course, it's a bummer there's no OLED, which in 2017 is shocking. But this is Tim Cooke's Apple now, and we're going to have to get used to MBAs and their spreadsheets trickling out technology over the years to keep us upgrading. The days of Steve getting on stage showing devices packed with the best Apple could make are over, alas.
But my main hope for 2017 is Apple has a serious fork in iOS and Apps for the iPad and gets serious about making the iPad a productivity device. Apple doesn't seem to get that what's holding back the line, and the reason I see more and more Surfaces on planes and in meetings, is the software.
It's not the lack of speakers or more microphones or the iPads needs more thinness. It's simply that it's harder to do a lot of productivity workflows with the limits of iOS and their first party apps. Moreover, a serious investment from Apple in iPad software would signal the app ecosystem their commitment.