Christopher Eccleston was of the best things about the 1st season of new who and it would be ridiculous not to have him in the 60th special.

Sure he’s doing work for big finish as the ninth doctor but bringing him back to the series alongside   
David Tennant, Matt Smith, Peter Capaldi and now Jodie Whittaker  This would be one of the best anniversary episodes of all time if you bring back Christopher Eccleston make it happen BBC