Better Grammar Check on macOS?

,Hi everyone,

I’m currently writing both a novel and various short stories within StoryMill right now. The thing that is really getting on my last nerve is the internal grammar checker in macOS. I may write the following sentence as dialogue: “Have you considered an organization?” The sentence sounds like a perfectly reasonable question to me. The problem is, with this and other sentences, the macOS grammar check will come up saying that “Have” may not agree with the rest of the sentence. Huh? MSWord has never gave me that crap.
Another thing: I’m sure my writing is filled with Comma Splices. If that’s macOS’s way of dealing with splices its pretty odd. Why doesn’t it do what word does and replace the second comma with a semicolon where applicable?
Surely some of you have ran into these odd behaviors with macOS and grammar. Is there a better app that handles this more fluently and with consistency? If so, I’ll extract my StoryMill content and paste it into that app and just do it that way.
Thanks all.