I'm closing in on LT Pt (I'll hit it early next year) and I use the Marriott Card only for hotel stays. At the moment, I'm chasing a 35K SPG Amex bonus. Otherwise, spending goes on CSR for me.

You've gotten good advice above and it really starts with your goals.

Finally, a shout out for mahasamatman - I just noticed the isotope reference in your screen name. You're one electron capture away from lifetime WS Pt status.