Separated inventory section for cycles was going to be implemented, in order to greatly increase the inventory's grid space and keeping cycles balanced at the same time. This feature has been canceled, at least for the initial patch, in order to cut into dev time. I'm also unsure whether cycles as is are staying or not.
Disabling charms from being sold can be done easily. Also the fact that it cannot be bought back, if I remember correctly, was related to a potential dupe exploit from older patches. Same reason why runewords and a few other items "criteria" cannot be bought back from vendors (they're deleted right away when sold). Blizzard always had the bad habit to just disable the technique used to triggeer the bug, rather than fixing the bug itself, which led to multiple same dupe exploits coming back with just different techniques used to achieve them. 1.13d+ patch for example has been plagued with dupe bugs relying on a bug in the code that handles "busy state".