I am honestly not certain if the extra attack thing transferred into 9th edition or not, but it seems as though you forgot an extra attack from your chainswords, which is a big deal, yes?
The main problem right now is that CSMs are living in a kind of rules limbo (I think--impossible to keep track of these days) where they don't have the extra wound the loyalists and Plague Marines and Thousand Sons go, so they just aren't very good anymore overall.
I could be wrong, though--it might be they got updates. Generally, however, basic CSMs are shooting units with some reasonable objective holding potential and they are solidly mediocre at assault.