Why should the +5 be free? The very few that got it as a drop from the original event worked, and died for it. It was not a 'free gift from a clicky'
I think you are mistaken in the value of the scroll - how many years have stat scrolls been in? and yet they are still in demand and sell regularly.
I also think just about every person who has an alchemist will want to get the amulet for their character - and who's to say more items won't be added in later publishes?
A lower drop rate will discourage many people from trying
First off, the +5 stat as an event reward should have NEVER been put into the game. The Event program was sworn to never put in OP items again (like LT Sash, Glads collar, ect). Events shouldnt hand out an item that helps one player become better than the next. And people died for it? The first night before it got hotfixed, all you had to do was make a ton of new chars and magic arrow the damn thing ONCE.
Stat scrolls is an ENTIRELY different beast. First off, a Harrower is popped 70% of the time for the fight. Secondly, you get a total of THIRTY TWO scrolls. Not only that, but its done in Fel, and includes a MUCH greater risk. Even then, 25 stats aren't guaranteed to drop in high amounts among those 32, and still only sell for about 3-5m each. There are many other things that factor in, that im not going to even bother.
You cannot compare Exodus and a Harrower.
A lower droprate will NOT discourage people from trying. I still see LOTS of Medusa groups, or peerless ones. Lots of people used to do Doom.
VS
The places with these new absurdly easy droprates.... Cove - Empty Despise - Empty
In a month Petra, watch Exodus be barren, and people posting and complaining that they cant do it because noone is ever there.