+1 for keeping the Biscuit malt. I've liked it when I've used it and think it would work really well in a brown ale. It'll give some depth to support the flavors from the chocolate and crystal malts.
Same goes for the Liberty hops. I've used them a couple times, but only in Belgian styles. Regardless, I've liked them and think they'd be good in a brown ale. I haven't actually used Willamette, so I don't know if they'd work well together. The Liberty will give an earthiness to the beer, which I think fits the style of a brown ale.
The wheat probably isn't necessary, though. If you brewed 2 batches with the only difference being that one had the wheat and the other didn't, I bet you wouldn't be able to tell the difference. Now, if you want the wheat to be noticeable, you'd probably have to increase the amount. With the crystal, munich, and biscuit malts, you shouldn't have any problem with body or mouth feel that would require using the wheat.
Side note: I'm guessing you started from metric measurements for the ingredients, because some of the amounts seem strangely specific when listed in pounds and ounces. If they come out to simple round numbers when measure in metric, that's great. That was just one element that made me immediately think the recipe was more complicated upon first glance. When I realized that you probably started from metric, and I paid attention to the percentages and other aspects, the recipe doesn't seem too terribly complicated.
I think if you cut out the wheat, you have a relatively streamlined recipe. And it should turn out pretty well.