YOU may not want to see any green, but maybe someone else does (like to make Augment kits materials)
YOU may not want to see any blue that you have purple for, but maybe someone else does (like for an alt while leveling where you happen to be short on the artifact materials).
YOU may not want to see "wrong" purples, but who's to say what's "wrong"? Yes there are stat combinations that are not ideal/optimal but maybe there is a tank with all his defensive stats soft capped and instead of making a "redoubt tree" purple with even more defensive stats he wants to make one with some offensive stat instead. Not a great example, but you get the picture..
I think the best way to do this would be the way you have your mission log. Have a little circle next to each one. Once the player decides they are done with that scematic....they can unclick the circle to hide it. Maybe have a tab on top of the scematics screen ....one says all schematics and the other custom schematics or something like that.
Ahem. Like the person I was agreeing with said. A way to toggle on/off which ones to show in the listing. So you still have ACCESS to the lesser oddball schematics, they just aren't (normally) mixed in with the good ones. And heck, if you frequently make use of them, don't even need to hide them in the first place.
(though instead of making an entire second "custom" tab, I'd just add a checkbox to the bottom somewhere that says "showall" then which shows all the schematics known with an additional column with the "show item" checkbox. Same general idea though)
And filter by quality doesn't help you filter out the wrong schematics. Such as a rampart shotgun. I'm sorry, now, there are some oddball schematics you can arguably make a case for in very unique situations. (though I'd still call them "wrong".) But there is NO argument possible in favor of keeping a schematic for a rampart shotgun around if you know any other purples.
(and P.S. There's enough good "non-oddball" schematics to fill up my 50 w/o putting up the oddball ones. Though admittedly, it's actually been some time since I was really heavy into selling my stuff, (before recent server merge, in fact) so it's possible the market is now super saturated with the non oddball ones, and the market is all about selling those 1 offs. Seems unlikely, though.)