In ESO, we have many many achievement furnishing items. For zone quests, for PVP achievements, for festival achievements. Why not with alchemy achievements too?
There are already achievements built into the game that are unlocked when you learn all 4 effects of a reagent. This achievement does literally nothing at the moment. Let's make it do something! Give us static items that look just like the nodes in the wild, that are purchased from the alchemist vendors!
Many of the alchemy plants are beautiful, as well as useful. I could see Water Hyacinth or Columbine being used just for decor in a flowerbed. Or perhaps you would like to set up an alchemy garden for your alchemist. Or, maybe you'd like to plant nightshade in your assasin's yard -- or in the Erstwhile Sanctuary.
Heck, why stop there? Why not have the other crafting nodes have a static version sold as a furnishing? You could build your own mine, or have a cotton farm! Grow flax in your garden just because it's pretty. Use logs to simulate driftwood on a seashore... the possibilities are many.