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Don't apply for ANYTHING (not even a CLI!) without talking to your mortgage officer immediately.
Definitely don't apply for anything until after you close on your mortgage. After that, it shouldn't be a problem. Just a note, business accounts generally do not appear on your personal credit reports (Capital One being a notable exception), however if you use your personal SS# the inquiry will appear on your report.
One other thing to note, there's no need to leave a balance on any of your cards. Just let a balance report, then PIF and your utilization will reflect it. Paying actual interest is just silly (not to mention it kills your grace period for the subsequent month as well).
You might run into some issues with some companies. I was denied a CLI on one of my csrds for too many recent inquiries. Back in Jan, I opened 4 new accounts.
With your scores and income it really shouldn't be a problem applying for those new accounts. After you get these new accounts you will however want to slow down and try not to app for anything else for 1 year.