I like this idea as long as it has to be an entire set and not just the individual prizes that aren't wanted. And only if it had to be a full set of 9 Reindeer.
If the idea is for someone like me to spend diamonds to purchase the set, this makes no sense. Dismissing one crap load of reindeer prizes I won't buy, to replace them with another crap load of reindeer prizes I won't buy means I won't buy.
However, being able to dismiss items individually in
hopes of replacing them with better prizes (for me) means that over the course of the event, I
might, emphasis
might, gather enough wanted prizes to spend the diamonds. Each replacement being subject to the same RNG means there's even a chance to replace the dismissed item with the same thing.
In my one completed sleigh, the Freight car and WT upgrade would go to inventory, the FPs and medals would be consumed (although I don't need them), leaving the Charming Cottage (I have 3 in inventory), The Winter Spire upgrade (I won't be building a second one) Champ Retreat (I get plenty of unattached), Tactician's Tower (I don't use space on city defense), and WW shrink kit would all go to the AD. No way I'm spending 3k diamonds on that.
Being able to dismiss the prizes that would go to the AD to
maybe upgrade them to something that wouldn't go to the AD means I
might spend the diamonds. No point for Inno to spend the money to develop it your way. It would net them even less diamonds from the reindeer than they'll earn this year. What's the point of that?