Can you elaborate? I honestly don't know his style and I'm just curious why you say that. Board consensus is Bunkley at NT since he played there in Denver. What makes you think he'll be a DE?
If I remember correctly, he likes the whole defensive line to play a two-gap style. In which case Bunkley at DE may be a viable option since his responsibilities there would be very similar to what he's done his whole career.
Someone like Richardson is more of a penetrator, so he may not be appropriate. But then Ryan is going to have to adjust somewhat to fit available personal anyways.