This year I kept Ramadan. No I am not planning to become Muslim. But I believe that the best way to understand something is through direct experience and I wanted to understand Ramadan so I kept it.
My initial thought before Ramadan was that this is a practice well designed for people who have to fight wars in the desert and so have to go periods without food or water, but that this practice no longer makes sense. Having experienced it, I have changed my mind and now I understand why Ramadan plays a critical role in Islam.
I want to compare Ramadan with shabbat. Both teach discipline. For Ramadan, this is obvious. Those who keep shabbat understand the discipline involved. The discipline of shabbat is to finish all chores on time before shabbat starts. But here the commonality ends and in all other ways Ramadan and shabbat are opposite. Ramadan teaches patience, one must wait for sunset to eat. Shabbat teaches one to hurry in order to be punctual. Ramadan teaches tolerance of adverse conditions because there is absolutely nothing that one can do other than wait to eat. Shabbat teaches that effort pays off because if you finish all of your chores before shabbat, your reward is a relaxing shabbat.
From this we can see that Ramadan is a good practice for a religion based on submission, while shabbat is a good practice for a religion based on struggle. So each practice is appropriately designed for the religion that it belongs to. I do not plan to keep Ramadan again, but of course I will continue keeping shabbat.