I agree we need a clinical striker/finisher and a decent goalkeeper. We also need a top class central defender and a left full back, indeed another back up right full would be useful as well. Then there's our soft centre with it's lack of creativity that needs attention too. However that's what Klopp should have dealt with and didn't to our cost, maybe he'll do something about it in the summer, or more likely he'll stay true to his own form and FSGs and sign a load of cheap overpriced prospects and we'll be still running hard to stand still! However and in the meantime we need most of all to find a few variations in our play. Looking at the fixture list the vast majority of the sides are likely to be bus drivers.
Klopp hasn't bought many 'cheap overpriced' (not sure how someone can be cheap and overpriced?) prospects though has he? Mane was hardly cheap and was an established first team EPL player. Same with Gini. Matip was free but was a first team regular in the German top flight so again, hardly a prospect. Klavan is an experienced player and is adequate as back up, again not a prospect. It's only Karius of those signed who could be classed as a prospect (and Grujic from the previous January).
I think we'll see a similar level of player coming in to address the positions required. Klopp has already stated that he's never been told that a player is too expensive and you can't buy him and that he doesn't expect he will. Unless he's lying I expect that is the case. He'll obviously have a budget to work to as most managers will apart from those at the mega rich clubs.
I'd also argue that our midfield is pretty creative too as we've not really struggled for goals. The problem for me is not having a Mascherano type in there to do the dirty work. That would also help protect the defence.