Pictoral Handstamps And Commorative Cancels On Covers

Hello, I was digging through some stuff recently and came across a stack of covers with pictoral handstamps and what I call special cancels, or maybe commemorative cancel might be a better description.I have thought about starting a side collection of these.
I don't knoe if it is something I would actively seek out or just keep them as they come along. Anyway, any opinions on these as collecgtibles, whether on covers or as cut corners?
Thanks
David
I just saw the posting in Topicals about these. Sorry about that.

Topical collectors love these. As a collector of King George V, I spotted this 1960's postcard in a junk shop and bought it solely for the cancel