I think they'd be better off running to Lancaster, Oxenholme, Penrith and Carlisle, linking those places (and Preston) with some of the stops which the Virgin/Avanti Glasgow service skips: MKC, Nuneaton and Stafford.
Whether it be Blackpool or, as you say, further north, the omission of Stafford from the proposed service is a disappointment. While Nuneaton will provide southbound revenue and satisfy demands for more London bound services, Stafford is similarly poorly served, with direct northbound services, and from the WCML north. I understand Stafford and Lichfield, as well as Tamworth and Nuneaton were to have been calling points, presumably when it was envisaged tilt would be available. Not now.