It does look like a strong squad, however the 2 positions that would be a concern would be GK & LB.
Should Mignolet be sold, Kelleher would then become Alisson's understudy. Whilst Klopp is not afraid to give Youth a chance it would be a worry were Alisson to get injured for any length of time to entrust the gloves to a relatively inexperienced kid.
The return of Karius should not be an option.
The LB position we are light in should Robbo get injured and a specialist LB as cover really should be sought.
Klopp does like deals to be done early so with coming up to a month since the summer transfer window opened, it is telling that we've not yet made a purchase. If Mignolet is sold then I do expect Klopp to have his bases covered 1st before allowing it to happen. Other than that it would seem we go to battle with an unchanged squad minus Moreno & Sturridge.