PROS: Excellent RB depth for a 14 team league.
CONS: Roethlisberger is passible in a 14 team league but still not who I'd want as my QB. Fleener is also a reach at TE, albeit one with upside. Panthers DST probably won't be great either, though that's less of a problem since you can always stream matchups reasonably successfully at DST.
OVERALL: Having that RB depth will hopefully help you address any of those cons in season if they're enough to cost you games. I think you can get over weakness at positions like TE and DST that won't be as important as RB/WR as long as your core puts up points, but I am concerned you'll need to upgrade Roethlisberger for it to be enough.