The higher levels in Marriott are based on Nights, not Points. That's why there's a special "15 night credit" listed. There are double night offers sometimes, but you'd still need to stay a decent number of nights to get Gold or Platinum.

You do not get points from reward stays. No circularity, sigh.

I agree with the other posters; Marriott is not the choice for you. 1 Marriott point per dollar is not as good as other cards.
The Starwood American Express is pretty popular for two reasons. First, a Starwood point is worth more than a Marriott point, since redemption levels tend to be lower. Second, Starpoints transfer to a lot of airlines. There's no Starwood status, but there is a current offer to get Gold without the card.

That said, I agree with Kate_Canuck. Hilton sounds best for you. The Surpass offer is what she says, with a fee of $75, free Gold level for one year, then Gold for $20K annual spend and Diamond for $40K.