What other central midfielders have you currently got?
I would dip in for Moussa Sissoko - he can become a capable playmaker but a better box to box.
Wilshere could slot in for Cesc, Jonathan Dos Santos, Toni Silva, Antonio Nocerino, Marek Hamsik [more expensive but worth it] could all be considered.
But I would need to see your lineup in order to give you a real - detailed response.