I have not bought or opened any as yet - this is a great thread and this is exactly what we should know as a matter of course for each of these events that we are now getting. If this is the win rate then I can see many of us just not bothering with ironite spends - I am by nature not much of a gambler though to me I think that it is our choice to use or not use free or paid for ironite. Not sure how much ironite I have actually bought but not a lot so I am not sure if this really is gambling or not - either way we should know what the odds are - or better still if we knew that buying say 20 would guarnatee a character (or some other number but a known number). Maybe a soul where you know the odds and where you get a chance at the character (known) but also some coins which add up to a point where you get a guaranteed character (like frontier coins).
I think 1% or around there is way too low for this kind of event - 10% is better. I mean I am able to farm all day so not a bother to me doing this kind of event but stil lothers are giving up a lot of time to try to get as many 'free' light souls as they can from the event - that takes time/effort and time is money (or this is they way I see it).
Either way transparency should always be to the fore. This helps to build a relationship I think and the devs, to be fair to them, do get inolved with us on this forum and also tell us what is coming up which you dont always get a lot of in other mobile games - well not the ones I play anyway.