Hello Welcome to the fourms. Nice looking project. how small is it?
IMHO there is certainly nothing wrong with mismatched components provided they work well together. There is actually some good stuff on there, the Campi HS and hubs, those Suntour shifters are still some of the best out there.
The rear derailleur is not bad for this either. Something looks odd with that housing stop can you take a better pic? it look like it was put on backwards.
Back in these days and still today bike companies mix and match components to get different price points. plus people are always upgrading and trying new stuff. Nice crank.
