As sorry, I see you got the new 2017 9.7 and not the existing Pro 9.7. The change in speaker configuration would be noticeable for sure. Do you use the Pencil at all? That would be another real reason to keep the 12.9 around.
Quoting from the other thread as it explains it all. Took my time with it so worth a repost. Copy and paste.
I'm going to annoy every 'is the 2017 iPad any good' thread creators and posters from this point on.
In the house we have my 12.9" iPad Pro. For how long I dunno... we have my wife's 9.7" iPad Pro. Now I got today... yup the 2017 iPad. I like the 'it's an iPad not tied to version number' appeal. I wanted a 9.7 after a year with the 12.9.
Comparison. Your a fussy s*** if the air gap bothers you. It feels good to type on it's creating this post.
Reflection. It's a bit more reflective but I set it up in a coffee shop near a window and did not cry. I forgot about it after I got to installing and setting up. It was a sunny day in Scotland.
Clearness of screen. No difference imo. It's the same resolution. Not sure what's going on with the poster with eye strain. By that logic all pre Air 2 must have hurt as air gap.
Battery. 80% out the box, 59% now. I have hardly left it alone. It's a good un.
Cheaper it may be but with all 3 here it's 100% iPad. The true 'upgrade' is 4 speakers. That's an ace feature. Keyboard is only something I use on occasion on my 12.9 and I could live without it. Pen? Forget about it for me.
Go forth and purchase. Makes me question my 12.9's price and I may sell as 9.7 is the Goldilocks of iPads. This too big, this too small, this... just right.