This event relies both on total of 9 beast rewards and available redeemables. What needs revamp is either (or both) sides of rewards, not event itself. Event itself offers items of value pretty much equal to cost, on top of that you get frags. Problem is except edo asuma (edo hiruzen team) there was no ninja that is actually usable, since danzo is a treasure ninja. For those who wanted edo asuma that was actually a good deal, even though majority of players propably could use something other of same value than chakra naruto fragment(s). Imagine having 2-3 seals or charm packs there, sounds much better right away.

Sakura always offered 7-10 adv refines for free. Or 2-3 rare meta ninja frags. Now with food drop rates up its even more. Historically it was always better than lets say wheel of fortune or lucky stars, where you could hardly ever get 1 good frag. It's not mission dealer level of goodies for free, but Sakura actually offers more interesting ninjas than mission dealer most of the time.

But regarding tailed beasts usefulness of free pulls- I agree. Those are non existant, since if you are spending you need to uncover whole plate anyway for 700cp and free draw doesnt offer anything anyway. Still if you spend there, you won't really be hurt.

When you think about it with free dices in the lucky board you can pick 1-1.5 60p ninja frag ( AOG konan for example). Sure, you can pick 3-4 refine boxes with ammount of points which makes it better than tailed beasts in terms of pure free stuff event offers. If you invest 700cp to uncover the plate (equivalent of 35 dices) results are pretty much the same, perhaps tailed beasts might even come out on top. All depends on redeemables inside.