Which short time window for first time visitors?

Hi. My young adult sons and I are considering a trip to Iceland next year. Based on college and work schedules, we are somewhat limited on times that would work for all.

First option: March 23-March 30, 2025

Second option: May 24-May 31, 2025

We would like to rent a car/self-drive but are open to day tours where appropriate. We would not want to try to complete the whole Ring Road in this amount of time, but we would like to make multiple overnight stops and see a fair bit without being pressured to drive too much in a day.

Pros and cons of each (I know no Northern Lights in May). Thanks much.