I was taking my blades to a mower shop to get sharpened and decided I wanted to do it myself so I went down the rabbit hole and purchased that American Standard sharpener. The first thing I noticed is how far off the mower shop had the angle, took a while and I ruined one older blade to get them back to the 30 degree angle the Toro blades come at. This thing is well built and is something you can pass down to your kids.American Sharpener brand lawn mower blade sharpener
I do have an angle grinder. To sharpen a lawn mower blade, use some kind of sandpaper wheel on the angle grinder?
Next I purchased a wall mounted balancer and sure enough they were all way out of balance and I mean way out.
Is any of this a necessity to get your yard mowed, of course not, probably way overkill for a home owner but I enjoy doing it.