Balotelli, Lovren, Lallana and Lambert have been disastrous, Balotelli is a good player in the right setup, but clearly not what was required at the time, and nowhere near mobile enough, Lovren is absolute shit, and was shit in the 5 or 6 months leading up to the transfer, Lallana is another average to half decent footballer, not a game changer, not better than anyone else at the club in his position, and clearly a waste of money, and Lambert was bought as the last throw of the dice battering ram, and seemed sound business, but more often than not gets put on chasing a game in the 88th-90th minute.
I don't want to retread well trodden ground, but that's £65m completely wasted, not to mention the £20m spent on a young exciting attacking midfielder/winger only to see him played as a right back or right wing-back.
I think Brendan is an amazing coach, but from a managerial perspective, his transfers have been utterly shambolic, the best setup is clearly a Director of Football, with Brendan as head coach, offering some insight into the *TYPE* of player he wants, but without having free reign, as he clearly has a problem identifying and signing the right type of player, both in terms of mentality, and of course profile.
I was certainly rubbing my hands with glee at getting back into the Champions League last year, but felt utterly underwhelmed at the profile of player being targeted when Lambert was signed before the World Cup.
(TL;DR version), Brendan to remain as a head coach, but with a DoF in charge of making signings.