I think that the flora is an important thing in videogames and especially in sanbox games. Besides the normal flowers,grass and ferns I would suggest usefull and dangerous flora.
Some plants could be bouncy while others could be climbed. I really like the idea of bomb flowers that can be picked up and thrown like in TloZ.
Then there could be dangerous plants like poison ivys or flesh eating flowers.
The different plants could be used in crafting too.
I really hope the devs consider adding different flora in the game