I agree with Kai's idea, keris unite. Comparison is a good way to learn this keris world. And sundang form -- even it is a Moro sundang blade -- is more keris than "pedang" (sword?). Why not use this type of blade as a comparison for keris form?
About the blade. I found this Karset's blade here very interesting. Especially the tail part of the blade -- I think I could not say it as 'greneng' -- really unique. A "birdlike" greneng, if we could say it. But overall, this is still a sundang -- with square tang (I choose not to say 'peksi'), and the bending straight of the blade. Typical a sundang form. And also the form of the blade's tip, in javanese (sorry again) we say it, the type of "ngudhup gambir" tip...
Anyway, Karset's sundang is old and beautiful...
GANJAWULUNG