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My answer to you is that your Amex obsession may have gotten worse since your approval.
I would sit back, relax, and enjoy the two new cards you have -- you're always going to be more likely to get better terms the longer you tend to the actual relationship.
And not to be rude, but do you have the spend to make concurrently spreading your rewards out amongst 4 cards beneficial to you? Especially since they'd all be going into the same pot.
With such a thin file, I would wait 6 months minimum before applying for any more cards AT ALL, let alone 2 more cards from a company that just approved you for 2 cards. Try and focus on getting SP CLIs for the time being. This includes a 3x CLI on one of your Amex cards.