Everything you say about Messi is true, I'm not in disagreement with. He's a genius, one of the best there is.That's simply not true. The year before his debut Barcelona were in crisis, finishing 6th, 22 points behind Real Madrid. Messi, with Guardiola, has been the catalyst for the greatest club side in the history of the game reaching their peaks. Messi was established as one of the best in the world as a teenager, Maradona not until his early 20's.
Also, there is no doubting what Maradona brought Napoli, but let's no pretend he did it alone and instantly. Napoli spent money on their squad and didn't win the title until Maradona's 3rd season with them and he was in his prime at age 26.
Messi has dominated League and Continental football for over a decade, since he was a teenager (I remember a teenage Messi running Stamford Bridge in the CL). Maradona had an incredible peak of maybe 4-5 years where he was untouchable. But then, so did Ronaldinho.
It depends on what you value, those high peaks where Maradona produced greatness or the longevity of Messi, who has been at the top of the game for over 12 years now.
As for the comment on the Argentina side, they aren't what you seem to think they are, they're an average international side that Messi has lead to 4 international finals (more than Maradona) and has had consistently awful managers and Gonzalo Higuain. Who, if he could finish his dinner would see Argentina as current World and Copa America champions.
His Barca side though was stacked with talent, this is impossible to deny. A crisis at Barca (and Real Madrid) have different meanings than any other football team, this crisis team were 2000 semi-finalists of CL, Semi-finalists copper del rey, 2001 semi-finalists UEFA Cup & copper del Rey, 2002 CL semi-finalists, 2003 CL quarter-finalists, there were not shit! Take a step back and make the comparison against us, we are runners up finalists and semi-finalists on the domestic scene and lets see in Europe, but we are seen as a very, very good team. I'm only bringing us up into this conversation not to compare the sides side-by-side but just to point out that they were arguably better than us today, the context of Barca in crisis is somewhat overblown I guess is what I'm saying, if only we were in as much crisis as them, I'd love to get to semi-final of CL. The subsequent years were of course phenomenal, but look at the team he was in, in every position you could make an argument the player was the best in his position in the World (always subjective and not always the case as the team as a whole is the biggest factor).
As I said, nothing you have written about Messi I disagree with. I do disagree with the context in which you placed him. The context is key in which Maradona should be viewed too, always difficult to make but having watched both in my lifetime the comparisons of the two era's they played in is night and day to me and why Maradona for me is the better player. (I can't make a case for Pele vs Best vs Puskas vs Eusabbio etc.. as I never saw them play).