Is there room for a few extras like phone and wallet?

Hi, yes, the side open pocket with a space for your phone, also you can use the top compartment for your phone and wallet.

Will this bag fit in a larger hiking pack? (60L)

Hi the dimension of this DSLR camera bag is 8.3 x 6.7 x 13 inches, I am assuming it would fit in a 60L hiking pack, you could measure the pack to see if it would fit. Hope my answer could help.

Hi! i was wondering if this includes any designated space for sd or memory cards? i don't see any in the photo, and i find those to be helpful.

Hi, there is a mesh pocket in the upper compartment specialized for SD card etc.

Can the dividers flexible? (60L)

Hi The dividers are flexible. There are the customizable dividers in this bag.

Can it hold my 12" Macbook?How does it work? (60L)

Top of pack has space for personal items or other essentials; lower compartment fits whole photography gears. A dedicated space for 10" IPad or a 12" Macbook.