I think the only way I personally would be alright with the rotational spells would be with a couple stipulations.
I'd like to see them at or just above current market value in hearts- stimulate the economy with a few spells reintroduced and at the same time get some donations in..
However, I would hate to see them in the shop for a long time. 5 days to me would seem like a lot of time- I'd like to see them in for maybe 3 days so there's not TOO many released back into the economy at a time, but still enough time to get some- similar to the bundle packs.
For me- if these two things were not taken into account it would just peeve me... But that's not up to me- it's up to the staff. :)