1. It depends on how many points you get. Usually you can take one. But the amount of points is different. Sometimes you get 32 points, others 20, 24, 28...

2. Only if the ninja is decent. But a lot of those are rather cheap. 2 Star fully SB Kushina for 2 point is hard to turn down, when you see wht else u get for 2 points

3. It got fair match making (players who are 1-0 play versus other 1-0 etc.) so there is no reason to show up late in order to dodge someone (as you might be able to in matsuri). Also, as you will find out fights can go 5 rounds and take 30 minutes+ and you have to do 8 of them in 4 days...which can be a lot considering the time window and the other events that you don't wanna miss out on. Be on time.