The secrets of Torah called מעשה בראשית and מעשה מרכבה I would like to suggest are learning Physics and Meta-Physics. And therefore worth spending time on. And I would also like to suggest how to spend time on them.
(1) As proof of my first contention I can simply refer to the Rambam who says this openly in the Guide for the Perplexed. To believe it is hard because you need אמונת חכמים belief in the wise. But if you have belief that the Rambam was wise then this is already established. A second proof will be my previews essays that show the Kabalah is a synthesis of Pre Socratics. It more fits the context of Medieval Alchemy than being insightful into the actual nature of things.
(2) The way to learn depends on age. But it is universal that the first moments when you get up in the morning are the most essential. Thus I say to boil ground coffee together with ground tea leaves as one. Drink this with Chalva or something and then learn for as long as this gets you. Then what I think helps learning after that is sit-ups and push-ups. This kind of exercise helps to continue learning. It is much better than jogging which causes one to not be able to learn afterwards.
[In NY they tend to drip hot water onto coffee and I don't think that is as effective as boiling it directly in a pot. Also my mother in law Rita Finn said to let it boil for 30 seconds. Or what I do since I don't have a watch I cover the pan and wait until the steam comes out furiously. I also do squat and stand as I wait. Try about 10 at first. That is something I saw on Russian TV and it makes sense to me even though they did not teach that to me in high school.]]
(3) If you learn the Ari as a great commentary on Torah and great synthesis of medieval thought then by all means do it. But avoid all later people that supposedly were explaining the Ari. I first of all consider it amazingly stupid for people to claim they were on the level or higher than the Ari. Especially since they are usually highly deluded schizophrenic manics as a rule. Next all mystic writings after the Ari all are from the Sitra Achra as a rule. [I mean Kelipa Noga as the Gra said.} That is their revelations are to put it bluntly are simply not true. But they are poplar because of entertainment value and emotional value. Not truth value.