I suggest this change. When a mob succumbs to the wither effect, or if a wither skull deals a finishing blow, instead of dropping as an item, the wither rose plants itself, and it wouldn't matter if it's in midair or not. The wither rose should also be more like a vine, growing up to maybe about 7 blocks tall. So instead of having an ugly crater, there would be a beam of wither rose sprouting, and while it's not as dangerous as a crater, would still be hazardous because it's a tall beam of wither roses. And anything taking damage from those wither roses will directly heal the wither. I feel like this would be a good change because the wither roses are kinda just there unless you plan to use them in a mob trap for a farm. They are not very involved or used otherwise. The roses sprouting upwards would also reference the beacon. Maybe even the flowers could look like nether stars.