I'm old school, so I'd probably tack up cork squares to fill the entire area up to the door height. That would give you plenty of room for reminders, a calendar, and of course - art!

Cork board with a whiteboard for notes at a comfortable writing height in the middle.

Cork can be covered with fabric to better match your cabinets or wall color.

I like lazy's whiteboard idea - magnetic whiteboard would be even better!

Here's a "pocket board" that uses oilcloth. (But I'd use some other fabric that wouldn't show the pushpin holes.)

http://www.marthastewart.com/267955/oilcloth-pocket-board

And here are a bunch from my Pinterest board.

One note: You could make some semi-substantial pockets on Homasote.

https://www.pinterest.com/pin/214835844702433769/

This one has some extra frames attached for calendars, write-on-wipe-off, etc.
https://www.pinterest.com/pin/525724956471882414/

This is a burlap DIY. The coarser the fabric you use, the less likely the pin holes will show.
https://www.pinterest.com/pin/302656037430108042/

This one shows the pockets holding things like a hole punch, etc.
https://www.pinterest.com/pin/302656037430108086/

Pockets of varying depth
https://www.pinterest.com/pin/302656037430107987/

This has pockets for pencils, scissors, and paper; plus a general "stick stuff up w/ pins" area.

This one has the Martha-standard ribbons or elastic stretched across and tacked to create something you can slip photos underneath, etc., to avoid pinholes.

w/ Homasote, you can sometimes even attach a hook or something. It's not the toughest material to screw into, but you could use a bolt and washer to reach through from the back.

Oh, and I wouldn't frame it; I'd just cut it to fit and either paint it or wrap it in cloth, and then attach it to the wall at the corners using anchors and screws/washers.

We have a metal front door that we hang all of DD's school stuff on. I LOVE the full sized door as a place to display her report cards, artwork, etc (temporarily), as well as putting up reminders from school. We've been doing this for years now. If I had your space, I would try to find the largest magnetic white board that would fit, perhaps even turned lengthwise, and use that. Then not only could you hang things with magnets, but also jot down notes with white board markers.