Not sure I agree with your points to be fair.
1. Injury prone players -
What is wrong with this point is that you have the implicit premises that injury prone players can easily be sold, ready replacements are easy to find, and one can be confident the new players won't be injury prone themselves. I don't think any of them are sound.
2. Players who don't perform -
This point is patently stupid. Firmino isn't our main goalscoring threat. He's a link player who gets through an awful lot of work and his work rate and combination play is a significant factor in the potency of our front 3 as well as how we link our midfield and attack. In terms of scoring, he's generally third of the front 3. Buying a different type of player (i.e. a 'finisher' as you suggest) would have knock on effects on the way we play and I doubt we would be as successful as we have been in the last 2 seasons. As it turned out, we did buy a player to compete with Firmino but he got injured, unfortunately. You've mentioned that we've got quite a few players who don't perform. Can you name who are all these players that aren't performing. Can you explain why, with so many of them not performing, how we've won so much?
3. Fringe players -
Fringe players are only a good source of income if you sell them for what they are worth. If you sell them for less than they are worth, then you don't make much income from them. With regard to the CB issue, we could have either bought a Lovren replacement (which I'm not sure we would have got much for 20m) or stuck with our 3 CB's + Fabinho as cover. Whilst Matip has had injury issues, I don't think anyone could have predicted that the other 2 CBs would get as bad injuries as they have had. So again, your point seems all very sensible in hindsight, but doesn't really sound like a good idea when you put it with information they had at the time they made a decision about it. The alternative is that we could have sold a few players, brought in a 20m pound CB who could have easily just sat on the bench behind Gomez, VVD and Matip for much of the season, would by definition be a fringe player themselves (being a third or 4th choice CB). That's not good business at all. The injuries were just bad luck.
4. Players approaching end of contract -
I'm pretty sure the club wants to keep hold of Gini and have made a very good offer commensurate with his abilities, and his age. You can't just force players to sign the contract. Maybe the player has his head turned, maybe he wants a new challenge, maybe something different. I think trying to cash in on him would be pretty hard because the other clubs after him would recognise that he's near the end of his contract and perhaps persuade him to sign a deal without trying to transfer him early. Gini's not such an outstanding player that other clubs are going to break the bank to bring him in. They'd rather wait to get him on a free in my opinion.
5. Central defence -
You're living in Football Manager World. It's not just a case of have a blank cheque and go out and sign whoever you want. The players that we are likely to be interested in are likely to be top class players who will stick around at the top even after VVD and Gomez come back. Such players aren't cheap, and exactly which club is going to sell such high quality players half way through a season? It's not that other clubs in the world just exist to service our transfer needs. The owners are wealthy but all of their wealth and interest is not in LFC. The club itself has to be very careful financially given what a pasting a lot of clubs are taking with the odd season. I think their tightening of the pursestrings is absolutely appropriate. That being said, you can't excuse them of being scrooges either. The spent a heck of a lot of money to get VVD and Alisson in. What history has shown is that if there is a sensible signing to be had ie a top player, decent price and ticks all the Klopp boxes, then we will get them in even if it costs a pretty penny.
6. General succession planning -
You are right about one thing, we do have a core group of players who have been largely responsible for our success. But I'm willing to bet that what you think is the core group is much smaller than what a lot of others (probably JK included) think is the core group.
The reason our success has been less evident this season is because we haven't had our core group together. There are the obvious injuries - Ali, VVD, Gomez, Matip, Trent, Jota, Thiago, Hendo, Ox, Naby have all spent significant time on the treatment/injury table this season; some more than others and I'm probably forgetting a few. Pretty much the majority of those players are core players. We haven't consistently had our 'core group' which is probably why we've struggled in comparison to how we finished last season.
I think another major reason is because of how condensed the season is. This doesn't give our players ample time to recover and prepare for the next game. Instead, they just spend their time on recovery and go straight into the next game. I doubt that we've had many opportunities to actually remedy some of the tactical issues we are facing because we're constantly just recovering from the previous game due to the congested schedule.
