One problem with most of the powered sharpening tools, unless you get a very expensive blade holder that clamps the blade straight: even a little blade warp creates very assymetric edges. The center of the blade has one edge higher, the ends have the other edge higher. Maybe you can improvise a blade holder with a vice and long pieces of straight material. Because Pro-Filer and similar tools are short, and follow the blade, it isn't as big a problem.
But I would like to be able to vary the ROH readily.
Of course you realize that varying ROH takes off a lot of metal, reducing blade lifetime. But yeah, that's very slow on Pro-filer, you have to buy a new kit for each ROH, and such major changes wear out your stones a lot.
You can achieve it by buying cylindrical sharpening stones of coarser grit. Not from Edge Specialties - they don't sell them. You have to go looking on the Internet. If I remember right, Pro-Filer stones are about 3" long, but I've used shorter stones (e.g., 2") from other sources a little bit in the Pro-Filer - they work fine.
Also, the old Berghman sharpeners, available cheap on eBay, came with coarser stones - though the oldest were pretty crumbly. In other respects they were better designed than the Pro-Filer, in that the gap is adjustable, though not as pretty. They were also a little more controllable - I didn't feel I had to tape the toe picks to avoid hitting them. But Berghmans only came with .5" ROH.
The main problem I've had with the Pro-Filer, though, is that it requires the blade to have an extremely uniform thickness along the length of the blade, and that requirement is not always met.
I always thought the tape technique, which the directions which came with my Pro-Filer advocated, was pretty clumsy.
Confession: All of my blades have been uniform enough that it wasn't a problem. Also, by flipping the stone around every few strokes, I can compensate for a gap that is slightly too large, or imperfectly centered. In some cases, I have enlarged the gap a little, BTW - for Matrix blades, if I remember right. In some cases, when I didn't center things right,
How I make simple home-made sharpening tools: I glue (dollar store) sandpaper onto dowel rods of the appropriate diameter. If I was really picky about ROH, I would have sanded the rods down a bit to compensate for the width of the sandpaper. You can even get between-standard-sizes ROH, and can picky different sandpaper grits. In principle 2 or 3 inches long is about right, but for a lightweight coat pocket took, I've sometimes used 0.5 to 0.75 inches. I'm not good enough at machine-shop type work to imitate the Pro-Filer, or the rubber hockey sharpener equivalents (which have gaps that are too thin for figure blades). So I take a sheet of leather or similar material (visit a fabric shop). I wrap the sheet around the stone, and pinch it around the sides of the blade. This is much harder to center on the blade than the Pro-Filer. It took me a fair number of hours of practice. The Pro-Filer and Berghman are faster for me to use, because I don't need to be as careful. But it is wonderful to have an emergency tool that fits in my coat pocket, and only weighs a few grams.
If your plating is not uniform, it may also not be the same thickness on both sides of the blade, which may mean that you are likely to create non-uniformly symmetric edges on almost any sharpening device. (Balance a Popsicle stick across the blade to check squareness. Or use a fancier mini-square, such as those from Edge Specialties.) So you will have to adjust pressures on different parts of the blade, by hand, to make it be symmetric.
I corresponded for a while with someone who used a smaller ROH stone than the ROH he wanted. He hand shaped the ROH. I tried it for a couple days. I lack the manual dexterity to do a good job. He worked in the trades, as a steel worker (he was also playing with making his own blades, and wasn't afraid of working at the temperatures needed to temper and harden steel), so I guess he was very good with his hands. If you are too, maybe you can do it that way...
BTW, in many places, you can join a community center machine shop fairly cheap. There are also "Maker" clubs, where you might meet someone with a milling machine. But another issue might be that if you mill it, you might remove the plating, to the point that it can rust.