Atanasov explains the advantages and drawbacks of using mechas in Earthrise, not the least of which is having your mecha stolen by other players. He states that vehicles can be placed in a 'pocketable' state when not in use, but can also be left in a persistent state (while unattended) for a window of time. It's that window that other players may try to use to boost it.
Atanasov also discusses how the environments in Earthrise will come into play with PvP, and the importance of tactics and strategy. He tells GameSNAFU, "Player killers should not only consider how to approach the enemy, but also the fastest route of avoiding the involvement of the AI-controlled security squad. Environments in Earthrise are complex and often require a lot of logistical planning when it comes to ambushes, escapes and such."
The interview also hits on PvE in the game, and how it won't shut solo players out from most of this content. Atanasov says it's only when a character reaches "the upper end of the mid-game to end-game spectrum" that the PvE content will be too difficult to solo. Still, in a sandbox game that will (presumably) allow for espionage and betrayal, trust will be important. Some players, Masthead expects, will opt to run solo if they don't feel they can trust others in their group and the developers want to keep the game accessible to these players.
The interview also drops more details on harvesting resources, factions, and storyline. Check out the GameSNAFU interview with Atanas Atanasov for more on what to expect from Earthrise.