SEEKING ADVICE ABOUT GRADUATING EARLY OR NOT

[SQM]

I am a Sophomore study in a university that is not strong in Math. I am able to graduate as a junior but if I do that I can't take any grad math course before graduation. I want to apply for pure Math programs in top grad schools. People told me that taking grad courses is important. Now I have two choice:
1. graduate early without taking grad courses
2. graduate in senior year and take some grad courses.
Which one should I choose to have a higher probability to get a better result in application?

[MathCat]

Stay the extra year and take some grad classes.

[SQM]

Thank you for your advice.