Be the best Hero that you can be on Hollywood.

Any Hero can have success on this map, but the following are almost always strong picks. 

• D.Va - Attack - A great disruptor due there being so much vertical space.  On Defense she can get back to Point A in a hurry if she dies. 
• Lucio and Mercy - Attack and Defense - They are excellent choices no matter where you are or which way you are going on this map. 
• Mei - Defense - Great on Point A, just stay alive.   She is also versatile as you work through the streets to Point B.   If you have a Torbjorn, you can boost him up to some excellen turret positions. 
• Reaper - Attack - This map encourages flanking.  Reaper is in his element.    On Defense he can disrupt and a well timed ultimate can change the game. 
• Reinhardt - An excellent choice for both Attack and Defense due to the confined "tracks" on which the Payload moves. 
• Symmetra - Defense - Her teleporter can save the day on Point A.  She isn't a great choice after that. 
• Torbjorn - Defense - Again, good on Point A.  There are a few "high spots" that are viable early in Defense, but there are better choices as you move through the streets to Point B. 
• Widowmaker - In the right hands is valuable on Defense, but weak players should avoid her. 
• Zarya - Attack and Defense - A solid choice as a secondary tank. 

Weak attackers will stall out at Point A.       

Cynical Nerds have an excellent video guide to this map.