How to attract new players!
-
The game really can't do better than the price it's at now at £3 per month, unless you're talking the "box" price of £24.99 (which I suppose has to be that high because there's nothing the devs could sell were it to go F2P).
As for Project Winter, that game is self-published. Ninja Theory is owned by Microsoft whose track record for supporting first party developers in terms of marketing is dire. A free weekend for a co-op survival game is great when nobody else is doing it, but there's loads of competitive multiplayer games that have had free weekends back-to-back and are continuing to do so - now's not the time for Bleeding Edge to do that to keep (more important than attracting atm) new players.