I've been thinking about this and I'd say that of the 7 players signed this summer, 6 of whom (Kean is primarily cover) are potential starters as well as providing squad depth. Dorrans offers a different option to both Howson and Hoolahan and Brady and Jarvis are both considerable upgrades on BJ on the left. Brady is also a very good LB option and Jarvis can also challenge Redmond at RW, especially as he has better tracking-back skills. Mulumbu was looking good before his injury and I think will be a regular starter when he's back. We need to see more of Mbokani, but I think he will be a regular starter in the future. All are capable of "making a significant difference to the first team rather than just add depth to the squad", so in that sense we have already moved up to the next stage.
The only real miss was at CB, but I suspect that AN decided that if he couldn't get a CB who would improve on what we have (given the demands his system puts on CBs), he'd wait until January rather than just sign someone who can cover.