I'm not saying that we don't have bigger issues but the reality is if we want to play a higher line more in line with Ten Hag's past then he is still an issue. At present we protect him very well, we defend deep and do not ask him to do work he isn't comfortable with - the biggest example of that is not asking him to deal with crosses at all, which is a huge improvement on last season because defenders were expecting him to come for crosses and he wasn't doing it, whereas this season defenders are dealing with crosses themselves so that micro-delay that was allowing strikers to get ahead of defenders, isn't there. In addition, he is sweeping a lot more than last season but it is not natural to him and you see him thinking about it before going out to the ball more often than not which causes a slight delay and hampers his chances of getting to balls that should be his all day - for example the occasions where Lindelof sprinted back into his own half on Tuesday to pick up the ball unchallenged rather than the keeper coming out for it. Like I say, these are issues that we are dealing with well as a team but it's a plaster rather than a permanent solution.
In terms of realistic options, Yann Sommer will likely be available again in the summer once Neuer is fit, David Raya will only have a year left on his contract, I think Robert Sanchez and Yassine Bonnou will be down to the last two years on their delas; Mamardashvili was available for a reasonable fee last year and has only built on his reputation this season, but even after a good season Valencia don't tend to sell players for ridiculous valuations, heck Ajax are about to sign Rulli from Villareal for like £10m. There's plenty of realistic options out there that don't cost the earth and would allow Ten Hag's style to be implemented earlier.