I've got an Opto Pure coming in the mail. That's been suggested to me several times. But, like you, I try to keep the molds down. My Lucid Judge is great for neutral approaches and drives and for anything that needs more fade, the Suspect is perfect. I carry 4 Judges and 3 Suspects.
Not sure if I'll have a use for the Pure or not, especially since the Gatekeeper is rocking my world for slower midrange. I shot my 2nd best round ever today, partly because the Gatekeeper has been money off the tee. I just keep getting to the basket with relative ease. A Pure may just complicate things.
Judges are great do-it-all putters. Right now I carry a fresh Prime Judge for in the circle putts and a beat Judge for longer putts and turnover drives/approaches. I also will sometimes carry a Lucid-X Judge for driving, depending on the course. My problem is that I *love* throwing putters, so it is really hard for me to just carry one main putter mold. I approach with a Berg because it is the shortest/slowest straight-to-fade disc I've ever thrown, so it ranges incredibly well. That eats into Judge duties. And as I've mentioned before, Envies and Proxies are incredible throwing putters...right now I'm bagging a Proxy as my main driving putter, especially in the woods. So the Proxy steals some Judge throws, too.
I do think you will end up finding a use for the Pure. Nothing against the Gatekeeper, but naturally dead straight discs are a thing of beauty, so the Pure should find a home in your bag.