Maybe with other games you'd be right. But with Madden, newer is not always better. EA regularly removes elements from its previous games and replaces them with elements that aren't necessarily better.
In no transition is this more prevalent than the leap from M10 to M11:
- M11 had Gameflow, which is supposed to be a better Ask Madden. But a lot of people turn it off after the first few games and continue to use Ask Madden. Why? Gameflow has a tendency to call unnecessarily difficult plays when you only need 1-2 yards.
- M11 has Locomotion, which is supposed to be better at controlling the RB, but it does this at the expense of removing control from the user. A lot of people report that certain runs are now unnecessarily more difficult than they were to make in M10.
- M11 completely removed the half-time show. M10 has the half-time show.
- M11 has a distinct graphical look that many people don't enjoy. While M10 seems to have meatier models that represent their real-life counterparts a little more realistically.
When you're dealing with THAT many questionable changes, I think it's safe to ask the question of what to get; especially when one title is $9.99 and the other is $42.99. IMO, none of those changes were worth an extra $30+.