Sure, what kind of decorations were you thinking? I got some in mind but always nice to hear from others.
As for the chests, The way they open plus the fact i wanted to have their position on the spritesheet account for the little "jump" they do when opening has them set the way they are, but if you wanna send a picture over to let me see the problem first hand im sure we can get it sorted.
As for the door, thats actually a good idea! Part of this asset pack is inspired by games like Celeste and Enter The Gungeon which both have those kind of doors your talking about, ill take a look and see how they do it and get my own take ready for the next update; Version 1.26 along with some other goodies. :)