Markakis makes some sense once the JUp and Gattis trades are complete. He is durable, can play RF competently (though not at Heyward's level), and should provide an OBP around ~.350 with some decent pop (10-15 HRs). He is literally a poor man's Jason Heyward, but without the recent platoon split Heyward has shown. He would slot in very nicely at the top of the lineup.
The problem is obviously going to be the price. He has already turned down a 4 year deal from the O's for $10M-$12M per year, and I don't think the Braves should be trying to top that offer. If he can be had for around 4/40 I think he would be a solid addition.