I think sometimes we get obsessed with wanting certain players, and I agree ideally a defensive midfielder would be a useful addition.
But the set-up of the team is probably more important. You hear the term 2 banks of 4, well if you can coach the back line and the midfield line to work efficiently, then keeping the distance between the 2 banks of 4 as narrow as possible, then it is hard for the opposition to play through the midfield. That takes a lot of work on the training field, but it is a very effective way of operating defectively.
However, let's not forget that since Liam has come in we have only lost 7 games out of 32 played, that is impressive, and we just need to turn some draws into wins.
It keeps being said the opposition is driving through our midfield, but defensively we are not far off one of the best in the league.