Thanos with the Infinity Gauntlet is all powerful. However, without that he's just a big, strong guy.
That being said, I know what they'll do now.
If they don't go straight to "The Avenger's 2: Electric Buggaloo", they'll make 4-5 more movies.
And, since the Infinity gaunlet is made of five gems, or 'rings', one for each finger (And thumb, of course), each Seperate movie could have a plot based on one of the gems, which are slowly brought together, until The Avenger's 2, when Thanos seizes them all to assemble the infinity gauntlet.
Now, that's all speculation....as is whether or not they'll add on new avengers for the sequel, like Wolverine, Spiderman, Antman, etc, etc.