Great explanatory video
My issue is what's the alternative? I adore our current team, but we lack something. A spark or whatever. And truth be told we won't find it in the transfer market, we might improve some weak spots (like buying a talent for RB), but that's pretty much it.
So, its basically going into the next season with our current squad (+some minor transfers that will happen with or without Messi) or with our current squad+Messi. The latter is definitely the more exciting choice, and Messi might provide that lacking spark.