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Not saying these are the absolute fastest locations in Scotland, but non-stop trains do seem to run at a "fair old lick" through stations such as Croy, Carstairs, Caldercruix as well as those skip-stopped on the section from Paisley Gilmour Street on the way into Glasgow Central.
In that particular area, I'd suggest Langbank - you get a couple of fast trains each hour, a couple of stoppers, and if your eyesight is good, you can see trains on the north side of the Clyde.
Other stations that are decent are Carluke, Lochwinnoch (although basically all you get there are 380s) and Lenzie.
Larbert for HSTs passing non-stop. Maybe too far away from Glasgow for the OP, but Dalmeny or North Queensferry for HSTs again, the odd Azuma and Voyager, although not passing especially fast, but of course there is also the view of the Forth Bridge!