Lovren - Sakho has only had one game, so we don't know how that'll turn out but a clean sheet against Spurs is a good start. Hopefully the proactive nature of Lovren means we can push up and more importantly don't crumble under pressure and start falling really deep into our defence.
Getting Valdes would really, really help with letting us play a high line. Sakho is quick and Lovren is no slouch (Aguero makes most defenders look like Jan Molby when he peels off the shoulder), and the fullbacks are pace as well, but Mignolet's reluctance and, even worse, inconsistency in deciding when to leave his line forces the entire line to drop back 10 yards.
Imagine how intensely we could press with a higher line to mop up the loose touches bought about by the pressing in midfield
Honestly, I feel like people have made up their mind with Sakho. Obviously there is a big problem with his passing in that despite it's general quality (hidden beneath the bizarrely awkward technique), the ones he gets wrong tend to be absolutely terrible, and turnover possession in horrendously dangerous positions, with everyone out of position.
But all it takes is for him to do that once in a match, and it's regarded as a shite performance even if he does everything else well and we don't concede from it. Kinda like Skrtel in his first few years imo.