I really like this guy’s wall mounted circular saw sled / rig. You can see it near the start of his video (10 seconds in, and the link has time index in it): Amazing Fine adjustment mechanism using screws - YouTube
I am seriously considering adapting the LowRider X-axis sled approach (pipes/bearings method) to create something similar…
Although I’ve got a set of linear rods with slide shuttles (with bearings) that could be used for it, I purchased that set for another project I’m planning on doing. And I’ve got a supply of electrical conduit pipe that could be used.
Here’s a screen grab of his setup. Notice he appears to be using a weight to counterbalance the saw + sled rig. If you look closely you can see the connection little wire rounding a pulley and attaching to the saw/rig.