I was playing today for my daily and I joined to 3 different custom lobbies (master difficulty and frenzy)
First lobby - Rail Line: Host started on wave 12, everyone started with 9.000 energy.
Second lobby - Blood Drive: Host started on wave 1, everyone had 11.500 energy on start.
Third lobby - Rail Line: Host started on wave 1, everyone with 10.000 energy.
Obviously I liked the 2nd one