Saddle toggles for mounts. Probably 9 out of 10 times it makes more sense for mounts to not have saddles, but this isn't an option.
Option to choose where visitors spawn in and/or a portal that teleports a visitor to designated node coordinates. The entryway for many homes is often not in the most desirable place for building. Setting the spawn or portal points would give builders a lot more flexibility with how they use their homes and in how they set the visitor experience.
Companion outfits. Currently companions use a default style instead of using any of the saved outfits. This is an immersion issue since the stylized companion you've adventured with doesn't seem to be the same one you can have in your home. How this would be saved might be complicated, but it would be worth the effort.
Emoting at pathing nodes. A list of options for what a special collectible should do once they reach a node would greatly add to immersive builds. This could be a short list of basic emotes or could potentially pull from the whole list of what the player has unlocked (adding immense value to collecting emotes). Being able to set pets to just be perpetually napping would be a great little bonus.
"Trusted" decorator permissions. Collaborative projects are currently a logistical nightmare, which is weird for an MMO. A sort of super decorator permission that would allow designated players to add/gift furnishings directly to a home or potentially remove furnishings would help a lot. Full placement and withdrawal permissions of unbound items could be one way to go about this (fully trusted), or a potential safeguard would be a storage box that players could gift into that could then be in the list of available furnishings to place, which then could also be the only Retrieve To option for trusted collaborators.
Just a few thoughts I wanted to get out there.