Don't know you're team, tactics, etc so I can't help.
I agree... but I'll throw in some ideas based on what I did with my Liverpool save...
Between 1st window and January window I spent about 31.5 million (first season) bringing in some of the best young players I could find (and some I just wanted to sign to see how they develop with good coaching). These players were:
Serge Gamwanya (DC/DM) (22K)
Joel Pohjanpalo (AM LRC/ST) (100k)
Bard Finne (ST) (free)
Ryan Gauld (AM LR) (525k)
Sieve Schrijvers (ST) (525k)
Mason Bennett AM LRC/ST) (3.5m)
Wellington Nem (AM LRC) (3.5m)
Adryan (AMC/MC) (875k)
Oliver Schnitzler (GK) (1.5m)
Stefan Simic (DC) (525k)
Adam Webster (DC) (675k)
Marc Muniesa (D LC) (300k)
Doria (DC) (525k)
Mathias Bossaerts (DC/DM) (5m)
Branco Van den Boomen (MC/DM) (4.3m)
Moi Gomez (AMC/MC) (3m)
Bryan Rabello (AM LRC/ST) (1.3m)
Of those players, some are quality enough to play for the first team right away (like Wellignton Nem, Moi Gomez, Marc Muniesa), especially in cup games or against weaker teams. I currently have the most depth in a team I've ever played with, with other youngster like Raheem Sterling or Suso getting a good amount of play time.
The one weakness the Liverpool squad has is striking depth, and I wasn't really comfortable with any of my youngsters being a lone striker (the system I play is a 4-3-2-1 or 4-3-3 with a creative striker up front). I signed Antonio Di Natale (my only over 21 signing all season) for 5m, which has proven to be a great decision (once he started to blend in to the squad). Di Natale doesn't start every game, but he is good enough to get the job done with I need to rest Luis Suarez. Di Natale also has a 16 determination, making him a great tutor.
So maybe that will give you some ideas. My team is currently tied for first with 2 games to play. My starting roster is mostly made up of players that are already there when the season starts (with the exception of Wellington Nem who gets quite a few starts, and as i mentioned, Di Natale).
Next season I'm looking forward to incorporating some of my 'older' youth players, and the future is looking bright for Liverpool. Also, the value of all the young players will in most cases more than double in a few years... meaning if you want to go after a big name player in a few seasons, you will have the cash to do it.
tl;dr: Sign youth players, the Liverpool squad is quality once you get rid of some of the dead wood.