You need to find a teacher that can teach you Identify above level 2, like the weapons officer in the citadel (first level, in the room with the good equipment you could not reach).
Level 12 sounds about right to head to act 2. If you want more experience and loot after completing all quests and learning from all teachers that you want, you can remove the citadel guard armour (if you are wearing it) and go back through the citadel killing everyone.
I thought the keys in the barracks open chests close by? There is a key in the parcours that opens a chest under General Bram's quarters, but it is not worth the effort to go back for that chest (random low level items).
The first summoning doll is a quest reward for helping cure the poisoned imp (after jumping down the pit and missing the haystack). If you return to the stairs where you entered the citadel, you can go back to complete this quest.
