I disagree-- look at the existing classes. Every class gets a huge, iconic feature at 2nd level-- Barbarians get Reckless Attack, Bards get Jack of All Trades, Clerics get Channel Divinity, and so on, all the way through Wizard getting their arcane tradition. Especially when it's a really multiclass-friendly ability like Action Surge or Cunning Action, it's almost always at 2nd.
Besides, 1st level is hardly sparse. You're getting two cantrips, Eldritch+Agonizing Blast (essentially), and whatever nifty 1st level ability your Patron gives you. You won't be bored.
The existing ones-- just noticed that I didn't specify "as the PHB Warlock" on those.Originally Posted by Quintus Vorenus
Don't forget, Maddening Blast is a 9th-level-spell equivalent, with a new save each round. (If anything, I think it's underpowered for 17th)
More pact/patron specific invocations are definitely on the table. I'm thinking that each gets four unique Invocations, one for each power level.