I think
#1 is almost a no-brainer. That's over $400 in AFs that just aren't valuable. The Gold vs Green is a toss up. The 1% dining isn't a game-changer, but what about grocery? If you're flying a lot, could you use the travel credit? I know that you already got free luggage through delta.
I kind of question what you would need the Platinum for if you keep the Delta Reserve. If you're flying through Delta the majority of your time and staying at Marriott with your Marriott cards, is the Platinum for breakfast at Hilton and an extra 1% or 2 on airfare?