I think Zion could also do well with improved writing. I don't expect Shakesperean literary devices of course, but I think in the future updates he should go back and fix some typos and grammar while also making upgrades to the flavour of writing.
I think the flavor will be a natural thing. I believe I got better at writing in the latest releases.
And about misspellings, I don't know what to say, Because this is what I do:
-I type in my e-mail, because there is one of the best online grammar correctors out there. It can easily catch things like then/them/than or though/thought.
-Then I send for Inez, who proofread everything.
-Then after it's include in the game, part of the team is dedicated to find misspellings. Which I correct before the final release.
I think some misspellings are unavoidable considering how much I write. The game will probably be 30h long by the end, if a person plays it for the first time.