I'm a newbie aswell, but I'll take a stab at some of the questions:
1. Channeling/Evocation and Ritual/Thaumaturgy all give 2 focus slots each. Additional focus slots can be gained with Refinements. Each Focus Item slot can be turned into 2 Enchanted Item slots.
2. Those are what's called Navel-gazing Maneuvers, placing a maneuver on yourself. They can, depending on circumstances be opposed, just like any maneuver.
3. Apparently, according to what I've seen here on the forum, the game balance tends to break down somewhat at higher refresh, so that might be a reason. Personally, I think handing out extra refresh a little faster during the earlier parts of a chronicle seems reasonable, at least if you're going for a "growing into your power"-kind of story.