I'm adding my voice to the chorus of those asking for easier companion management. I'd prefer it if we could add party members outside of camp, like if we could teleport them to us or something. I'm always adding and dismissing Astarion for his skill in locks and traps, and constantly going in and out of camp (and clicking through several lines of "are you sure" dialogue) is getting old. Plus, I've learnt that there are some quests that are on camp timers, like the Nere one.
And, yes, please let us view and manage companion information and inventories even if they're not a party member.
Also, a minor issue, but in the controller for PC version of the companion information screen, the companion's approval tier is shown, but not the numbered rating as in the k/m version. Please include the numbered rating in the controller version, some companions (just Astarion, again) really need delicate management of their approval.