I'm quite new to the software but one of the things I saw interesting was the fact that you can set global variables and perhaps those ones can be translated into playmaker global variables.
You can also script conditions but I found that one more difficult to translate into Playmaker environment. According to their site, this is what the integration with Unity offers:
Automatic data import
Convenient access to objects and properties
Fully customizable flow traversal engine
Fast automated script evaluation
Localization via Excel®
Easy to use Unity components