I know folks love the ME Super, which is why I tried a couple. Frankly if I wanted another camera in that line I'd just get an MV ;-)
The OM2000 is my favourite Cosina variant, for the selectable spot metering. Otherwise it's the FM10. These bodies changes a lot in the 80's and the older the version, the less polished they are. The late versions from the 90's like the FM10/FE10, OM2000 and similar are the best experience because they have better grip designs and the wind lever locks the shutter. I do kind of dislike the 'spaceship' looks of the late CS-1 itself and the late Vivitar versions.
Note the T60 is unique as well. It's the only one with a horizontal travel shutter.
If you're really looking for small, the OM2000 is the way to go, followed by one of the late K variants (Ricoh KR-5sv or late Vivitar/Cosina branded ones), specifically for the small lenses available. The FM10 with the Series E primes is also a small setup, but be aware the Series E 28 is a dog, the 35, 50, 100 and 135 are all quite good and the 100 is unusually small and light for its focal length.