Starch is one of those old standbys -- better than flour/water, and not quite as good as (IMO) methyl cellulose (which is hard to find and rather expensive). 

I was reading a book on making Mexican pinatas, and an old pinata maker said starch was preferred, but flour was cheaper.

I know when we did PM as kids, the attitude of the teacher always seemed to be "thicker is better", but I have since discovered that that is not true.  With starch (which can vary a bit among brands), I usually mix it half/half with water.

The one thing I don't care for with it is the tendency toward brittleness when dry, producing small flakes. If you have thin "wings" (etc) that may flex, it may be a minor problem, but once it's painted and sealed, that really isn't a problem.

Starch is hygroscopic (it absorbs water), so you will want to seal it in humid climates. If you are painting your project with acrylics, that should provide enough of a moisture barrier to protect from moisture in the atmosphere, but it won't be good enough against rain outdoors.

But it is still a very usable adhesive, and doesn't attract vermin.

Sue