OK, Schematics isn't the tough part of your project, once you have working & tested circuits of each module. You see, schematics & routing ain't challenging for me but Placement, tht's really kill your brain's out.
You have to iterate several times even after you start routeing the board, to get best results. and don't neglect DFM.
I was figuring out, what would be the best pin placement. I was looking for way such a that it would be flexible to access ANALOG & DIGITAL pins from both side of the platform.
I think this is my terrible idea, as you can see, air-wire flying all over the board, it is going to be challenging task to layout this board. Haaa! Auto-router might die routing this.
Also, I have to keep in mind the from-factor of below 10cm x 10cm in dimsens..
Thanks to my Internship at AMI tech. where I was involved in development of wireless Automatic Meter Reading systems. It's there I learn to play with Wireless modules-protocols like Zigbee, Sub-1 GHz.