Griezmann is without a doubt a world class player. No sane person can deny that. An elite player in fact and in my top 5 of best offensive players out there currently.
In isolation his purchase is great as well. The club bought a proven goalscorer, playmaker (in terms of assists and linkup play which is one of the very best out there), a very versatile and hard-working player. In his prime with at least 3 very good seasons left in him if not more. The transfer fee is not too outrageous either for a player of Griezmann's quality and given the current state of the transfer market.
The problem will be how to fit him into the team, if Suárez as expected won't warm the bench most of the time, which is extremely likely to occur with Valverde around.
The good thing however is that Griezmann could be used in various tactical setups. As a left "winger" in a 4-3-3, as a false number 9, as a secondary striker in a 4-4-2 and theoretically as a right "winger" in a 4-3-3 as well.
If he ends up benching Suárez (hopefully) he will surprise many people with his great aerial ability (I would claim that he is superior to Suárez on this front), his link-up play (vastly superior to that of Suárez) and his presence in the box. Can't see any reason why Griezmann could not score 30+ goals next season if securing a starting spot which I cannot imagine that he will not do.
If Neymar ends up arriving, as I expect (not something that I hope for at all), that frontline should be made up of Neymar, Griezmann and Messi. Anything else would make no sense.
