We may sign another player falling into the "talented youth" category and for me, that's great. We should aim to develop and attract the best young players and have the best facilities to entice them.
Who knows how it works precisely but IMO Walsh should have the freedom to bring any player straight into the academy and U23 setup.
Obviously Koeman should have a veto on who is added to the first-team squad as that is his responsibility.
I would expect Walsh to take a long-term view and Koeman to be concerned with the short-term, such is the nature of management.
Lookman would seem to be a good example of a more pragmatic middle-ground between long-term planning and short-term expediency. His development will no doubt be managed but I think this particular type of signing is rare enough - we paid relatively highly for him and he will probably see more game time than normal for someone of his age, let's hope we have bought another diamond there.
Signings in the main tend to be at two extremes - younger "potential" type signings who could spend several years before making the first-team squad, if at all, and the more expensive "ready-made" and invariably older signings, early 20s and above.
I think a good transfer strategy maintains the right balance between both elements. We will clearly not be able to lash out £30m to improve our options in each position. We need a mix of youth and experience, of players who can give us 10 years of service, and others who can be developed and sold at significant profit to provide the flexibility we need for FFP and to allow for renewal of the squad in 3 or 4 year cycles.
It's interesting with each signing we make, that it seems easy to identify those led by Walsh and those by Koeman. They are all Everton players, it's the balance between the types of signings we make that should prove fascinating over time.