Total international traffic in the last 3 months at LPL & MAN combined is down 2.1% vs 2011. Rest of the UK is down 0.2%.
Until the economy improves and / or APD is lowered for regional airports, there's not much hope of traffic levels in and out of the North West growing massively.
Instead weaker operators will go (bmi baby) or downsize (Thomas Cook) and stronger carriers will use their leverage to shift capacity to which ever airport gives them the best deal or where they can exert pressure on weaker operators.