It wasn't very difficult to do the ties, after all.
I planned an (obviously) very open weave, and intended to add some black (still paper yarn) figures here and there.
The plain weave was ok (sort of; didn't dare try opening the sheds "too much"). So I added a sample figure, in black, in a 2/2 twill.
Ok, maybe it would look better later. Did something else for a couple of hours.
It did not look any better.
So: plan B: add some threads here and there, to get a "spaced-and-crammed" variant. As I wasn't very keen on doing all the tying again, I added 4 ends at each selvage, and some in the middle.
Wove a hem of sorts.
Wove the first "window":
When I suddenly saw... (click to enlarge)
I'm back to "now what?", I suppose!
My thoughts were:
I have heard, and can easily believe, that if paper yarn is woven wet (moist, I guess), the weft will stick to the warp by itself.
So I chose the most open wooden reed I had (which, incidentally, is the most open reed I have, regardless of meterial - about 20 dents/10 cm) - it was the most open reed, and it would withstand moisture. A typical win-win, I thought.
Did not bother to count/inspect the whole reed, which means I did not see the dents were more widely spaced on the right side than on the left... (I suppose it is all right for tightly woven rag rugs)
Maybe I will think of a plan C, tomorrow. Or maybe it is just "charming"?