Perhaps not much as "lacking complexity" but rather "showing restraint" in order to allow the blackberry honey to have noticeable prominence in flavor and aroma. If kegging (or bottling), you may wish to save some of the blackberry honey for late additions to the fermentor and/or priming in order to better retain the aroma.
Similarly, as tempting as it may be to change the grain bill (e.g., small %'s of honey malt, victory malt, or vienna malt), you're probably best to leave it as is unless you're looking for moderate malty sweetness. I think you're going to get enough body from the malto-dextrin powder. The wheat and MO malts should provide enough malt structure to support the honey and hop bitterness without overwhelming it.
I'm not much of a Wilamette fan (flowers, fruit, earth, spice aromas)--it is OK, but I personally think Summit (robust citrus--orange, tangerine, grapefruit) or Mt Hood (Hallertau hybrid, clean, mild floral/spice/forest aromas) would be better choices. I don't like "earthy" flavors or aromas--that's just my personal preference. I'm also a fan of keeping the IBU's on the low end of the style, as well, especially with honey wheat beers.
Clean yeasts like WY1056 or WY1272 would work well, IMO. I have no experience with WY1010 American Wheat.