Okay, as a Person who follow this game before Carl route done, I highly recommend route to play as 1.Carl 2.Leo 3.TJ 4.Flynn 5..Jenna
Why? Because if you jump straight into Jenna route it'll ruin some 'plot'. The important thing is a puzzle and hint has been reveal slowly in each route. Think of it as a CHAPTER.
OH and before you play Jenna route besure that you finished Echo route 65 first! ;)