Understand that these benefits are fairly hit-or-miss at Marriott.

1. As a Marriott Gold you get a lounge breakfast only if a) there is a lounge and b) it is open. Limited service properties do not have lounges. Many full service properties close their lounges on weekends. Offering a full breakfast as an alternative is a choice made by the property. It is not a program guarantee. Also, c) the quality of lounge breakfasts varies between properties. Some offer tasty spreads including eggs, breakfast meats, fresh fruit, and a variety of breads. Others offer limited selections of poor quality.

2. Late checkouts are also hit-or-miss. First, although MR uses the word "guarantee" in the headline the T&Cs state it is "space available". And "4pm" is "as late as 4pm" (emphasis mine). MR elites routinely report that getting a late checkout requires arguing with the front desk. My normal experience is:

"Hi, this is Darth Bimmer in Room 1234. I'd like to get a late checkout."
"Sorry, there's none available."
"Even for a Platinum member?"
"Let me check.... Okay, we can do 1pm."
"You don't have anything later? Like 4pm?"
"No."
"Okay, I'll see you at 1."