I believe a fair compensation would be to own up to the mistake and host the event in its original state.

This gives everyone equal chance/opportunity/benefit from the "Sale".

The only victim here would be Oasis of course for selling items at heavy discount, but its not like they are free, you still need to spend. And with those good deals, players will likely pour more money into it to get a piece of the action.

As for people with 5kage Masked man complaining that people are getting it at a lower rate. I cant speak for those people as my opinion would be biased since I dont have 5kage masked.

Sakura event: change back to 10/sack
Do not modify the Onigiri's drop rate

You can adjust 5k Madara's cost
Ok with sailor/suit package to not re-appear as that seemed like a real bug with the pricing

I mostly just care about the sack price since by protecting the 5k Madara's pricing, they are indirectly making everything else 100% more expensive and I think that is making the sakura event extremely undesirable.