There's nothing odd about that grist. All of the grist ingredients are Traditional and therefore Good.
On the other hand, your grist has 0% grain with husk matter. You will
encounter a stuck mash. If you don't add some husk matter, in the form of rice hulls, you will find it impossible to lauter this grist.
Now, the hops profile is
completely nuts. Flavor and aroma hops are inappropriate in Witbier, Imperial or otherwise, IMNSHO. BJCP says, "A low
spicy-herbal hop aroma is optional, but should never overpower the other characteristics
." Also, "A spicy-earthy hop flavor is low to none
, and if noticeable, never gets in the way
of the spices." (emphasis mine) Your hops schedule is designed
to overpower the spices.
Traditionally, Wit brewers used old, stale hops - we're talking three years old, here - for bittering only. The best Witbiers use low-alpha noble hops in a small bittering charge. The flavors and aromas come from the spices and yeast.
That said, this is homebrewing. You can do whatever you like.