I strongly agree with the above. Worth reading Cleons 4231 thread that covers use of Attacking versus Standard very well.
The 4123 formation is pretty top heavy still and asking your FBs to overlap the IFs may be leaving yourself wide open to counter attacks out wide with your FBs getting caught ahead of the ball. I think this formation is very tough on your FBs & CDs as the FBs can be very exposed/uncovered and your CDs need to be very strong in the air to help deal with the resulting higher volume of crosses.
Playing with a club with a high reputation such as Liverpool will lead to you coming up a lot more against teams playing counter with 4141or 442 type formations and that sort of formation with speedy wingers maybe causing you some problems. It would be interesting to hear if that is the case? I particularly look at the left side of your formation which looks susceptible to counter wide play. I used 4123 on my Bremen save recently and I found as our reputation rose we were finding trouble winning some away games due to the teams doing this. I have had some success from moving to 4-3-3 by pushing my DM(D) up into the central MF role as a BWM(D or S) and creating an extra man in there. I wont go 433 against opposition tactics employing an AMC though. That said, I play standard/flexible and my overall player roles, etc are a fair bit more conservative than yours. My tactic looks more like:
WBs(D) - CDs(D) Note; one or both WBs n support at home
BBM(S) - AP or DP (S)
W(s) - IF(S)
Overall, a fair bit more conservative, but this is a starting base that I would tweak during games if I felt the need. I would always be more likely to adjust roles as step 1 rather that mentality, etc.
Hope this helps and good luck with your save.