I actually disagree with this. The way it is now is stupid ya but having the primaries be staggered could give the chance for otherwise unknown candidates to gain traction. Since a national campaign is hard to pull off for a small candidate but if they can focus in on 1 state they can actually make an impact and then get national attention by doing well in that single state.

Now in saying that i dont actually think liberal democracies are a good thing. I prefer a model like China has where you have elections in sequential levels with the lower level reps electing the higher level reps. It allows a more close connection to the people representing you and keeps elections small so that small candidates can make their case easily. And prevents sensationalization the way american elections are. I would combine a system like this with the ability to enact direct democratic actions via ballot measures on specific issues that people are really invested in.