Don't disappoint f2p again, guys.
Seriously, if you put for anniversary something that cannot be gained at all by every free to play person by taking in account only the resources they can get during the anniversary week you will make them unhappy again.
So, please, don't put something like jonin minato in that week at 12k coupons if almost no free to play person is able to gather in that week more than 1500 coupons. They would just consider it your n-esim joke with them.
Just wait and put him in the following week if you want.
F2P people expect from anniversary to get a ton of GOOD things for free by the events or hokage mail direct delivery.
And so just give them to them.
Is not the end of the world if for one week you just gift them with easy gainable advanced refinement runes, mood scrolls, advanced threads, tactics pages and so on. Don't plan any single event where potential rewards are dangos, shapeshifting cards or cloths. They are really annoyed by those. Free to play people once in a while want events where whatever happens they win something that surely for them is good.
And they want to be able to get for sure, with some effort, at least one good ninja.
Why not give something like a kage optional gift pack just with common rare kage treasure ninjas in it like pain optional gift packs to them? We are going to get more treasures, kage metas are going to be no more updated and to get a very specific ninja from that treasure could be extremely hard. Those are things that would make everyone happy.
Anyways, this is just my opinion.