I think Spurs have got a great deal here to be honest. Walker is very average and getting 50 million for him is a good coup.
The problem is Spurs are god awful at reinvesting their money (see all the crap bought with the Bale money, followed by the last transfer window)
Spurs are a good team, but they both lack the ambition and the know how to be a truly special team.
It just shows when you see fans absolutely delighted at the fact that they've been in the top four a couple of times, it's not a big club mentality.
But that's by no means a bad thing, not every club can be a huge super club that takes in trophy after trophy. Spurs can and should be proud of where they are, but they probably won't ever be much more than this.
As for the argument that they're not selling their star players, there's only really Kane in my opinion who is truly worth grand sums of cash just yet anyway.