For members of any ARSOF Branch, what were some of the discernment questions you asked yourself before applying?

Go with what you are most interested in. Don't worry about the conventional forces collapsing due to the absence of your personal leadership--they will manage somehow.

My question back to you would be - What do YOU want to do?
Once you answer that question, that will be the top of the list choice and then order the rest of them from there, using the same question.

Do it! Best career move in my life after OCS.
SF or CA is your choice, both are needed by the Army. SF is supposed to be training foreign forces for fighting our wars. These days it is a lot of direct action, due to optempo. Someone may correct me if I am way off base on this.
CA will set you up for working with SF that are actually working SF missions, but you'd be working with the population not in the militant sense. CA can set you up for a State Department gig later on in life.
When I went to CAQC in 2007, Active Duty and Reserves went together. Many of the Active Duty Soldiers had tried SF but didn't pass selection and CA was their second choice. I wouldn't read into the fact they weren't selected, that can happen for many reasons, a lot of these guys were injured during selection, etc.
I loved CA, variety of training, missions, opportunity, advancement namely 2 majors in a company, rather than battalion in combat arms.