Q: ipad air 16g or 32g?

Since the iPad's storage cannot be increased, buy as much as you can afford.  Better to have and not need than need and not have.  Plus it will be worth more when you sell it.

It would be very difficult for any of us to help you, especially with the amount of information you provided.

You cannot add storage later.  So if you can comfortably afford the bigger one, go for it.  If 16GB is what you can afford, you can always limit your storage use to fit within that constraint.

Since you can't add memory to an iPad, the best option is to buy the one with the most memory that you can afford. So, if you can afford the 32 GB one, get that one. You may not need the space now, but you will have it if you do need it in the future.

16GB vs 32GB vs 64GB: Which new iPad storage capacity should you get?

http://www.imore.com/2012/03/08/16gb-32gb-64gb-ipad-capacity/

How much content will fit on my iPod or iPhone?

http://support.apple.com/kb/HT1867

How Much iPad Memory Do You Need?

http://ipad.about.com/od/iPad-Tutorials/a/How-Much-iPad-Memory-Do-You-Need.htm

 Cheers, Tom