I just CCU'd my Avenger to a Cutlass Black and man it is an ugly ship. I was increasingly unsatisfied with the Avenger, not because it is bad but because I am looking for more of an I-War experience than a Wing Commander one and a bigger ship fits the bill.
Not sure if I will keep it or exchange it for a Freelancer or something else in the future. Don't plan to put significantly more money it the game until it comes out. I have had the Avenger since July 2013 after I melted a 300i package.