So i just cleaned up my Season 1 Mail, i have about 600ish Keystone of Trails. I accepted them all from the mail. Since i have too much i decided to delete some. I forgot that you can delete, sell or drop the stone. What am i going to do with 600ish keystone? They're just sitting in my stash and the worse thing is they only stack to 100 instead of 5000.
Keep them, there is no way of knowing what the future brings for the brave souls fighting in Sanctuary.
They could easily remove or drastically change the trial system, you may find it easy to get different levels of keystones quite fast, and you may regret not having them. Keep in mind that you have to farm normal rifts in order to get them. Even if you have 1000 keys, you can still burn through them quite fast if you only do GR. And once you start doing these, and get close to wasting them, you may bash you head on the table when thinking you scraped them and have to do normal rifts again.
And this is coming from a guy that still has most of his gems under 20. I hate GRifts, but I keep the stones.
The trial system is idiotic. The least they could do is allow us to use more than one (say 10) keystones for a single trial, this is a very minor change and it would help tremendously... When a player has to make a new character just so he can delete keystones, they should know something is not right and change it right away (they don't though).