He was £31 million cheaper because he was an unproven quantity. He was younger but Ozil was and still is at an age where you don't really worry too much about pumping a lot of money into a player. Ozil was 24/25. He is not a much better set piece taker, he is a better free kick taker whereas Ozil has better delivery from a free kick and corner.
And as for much more versatile - he can as a number 10 or out wide like Ozil can?
How do you know he clearly has a better attitude and demeanour on the pitch? That's baseless.
Only 2-3 months ago he came under widespread criticism for his poor form. That was only a couple months after his manager came out and said his initial early season poor form (and end of season poor form from the previous season) was because of length contract negotiations. Hardly a great indicator of good attitude.
Eriksen is an inconsistent player and I've had plenty of my Spurs supporting friends tell me the same thing. He's either incredibly good or plays way below par.