UE4 needs to support all of these features out of the box. If the indie developer is the next big market, a lack of multiplayer features might be an Achilles Heel.
Biggest reason why just anyone cannot make an MMO, the marketing is almost as big as the game itself (although that could be true for any game). There are a lot of great, free MMOs out there already which makes it very hard to successfully maintain one yourself.
I would encourage you to jump straight in to UE4’s multiplayer features. Using Save Game Object to storing a Worldstate Snapshots locally on the UE4 Server can be used to maintain persistence. After I complete my work on EyeManga3D, I’m jumping deep into UE4’s multiplayer/networking to work towards a VR MMO Virtual Mall for the next phase of the TheGameDevStore.com.