If you've gotten 5/5 Campaign from doing HM EC and Nightmare Pilgrim then I'd suggest leveling an alt.
At this point once you've got HM EC 16-Man on farm you've beaten all the PvE content
Pretty much where im at now
I have 4 50s going on a 5th...pretty much have leveling down to an art now at this point lol.
I seem to recall an announcement a few weeks back that there was going to be a new Operation and a new flashpoint coming out towards the end of the summer.
EDIT: Nevermind thats for later in the year. sighh.