Beyond the "super carrier" role, which has already been discussed, I'd like to add my voice to the "it's cheap" merits...
I'm still desperate to be able to run a 3-ISD-I list with Motti, as below:
My opinion nowadays is any fleet without a serious anti-bomber (Rhymberball/Fireball/Jan Ors Scurrgstravaganza/B-Wings+Yavaris/whatever) plan is going to get its lunch eaten. I kicked around a few 3 ISD plans prior to the tournament but even running completely-naked ISDs + Motti means you've only got 5 TIEs running interference for you and no reliable plan to get use out of your black dice.