Looks pretty good. What bit, feed, and speed are you using for the bottom pass? I think it is going way too fast for Poplar. Notice that on the straights the wood appears to be ripped out in sections. This is not happening on the cuts with an arc in them. The CNC linear motion runs a lot slower in these curved areas. Hence a lot more cutting, less ripping in these curved areas. A Downcut bit can also help quite a lot.