While it's finished (congrats), lifting one end of R25 yields vibrato. So,you may want to consider popping a hole and installing another toggle for a second effect. Given that most commercial flangers that use FET switching simply cancel the wet to "bypass" the effect, they can't easily cancel the dry signal to produce vibrato. Seems a shame to forego the opportunity to have it here.
BTW, the "stereo" is a little different than some other stereo flangers. In many instances, the two outputs are used to yield negative and positive flanging, by combining the wet with dry for one output, and inverting the wet to combine with dry for the other. Here, wet and dry are combined for a "master" signal, which is fed to one output and inverted and sent to the other output. That arrangement should not yield any tonal difference between the two outputs, which seems a bit of a waste of an output.