Another thought on aerodynamic improvement, instead of making the pointy nose out of wood (thus limiting how far you can go without stretching your plywood, and also limiting the internal volume), why not make it out of foam?
I'm not the best artist in the world, so I wont torture you with my MSPaint skills, but I wonder how the following would work:
Using the standard weekender design, cut a piece of 3/4" plywood (or use scraps pieced together to make a rectangular frame the same size if weight is critical) to match the front face and install draw latches on it and the weekender body (at least two on the top & bottom, with maybe one additional on each side, with the stationary side of each latch on the camper to keep the appearance clean). I would use at least two index pins projecting from the trailer into holes in the new plywood piece (3/8" or 1/2" dowel? only has to stick out 1") to make sure you have it seated properly and the draw latches do not pull it out of position (maybe some sort of hangers so it wouldn't fall off if unlatched and you could attach/detach it solo?). Then use industrial adhesive to attach foam panels to the plywood and each other, using a hot knife to carve them to the proper shape, finish as a standard foamy and paint to match the theme of the trailer. The number of foam layers would affect the top/bottom angles you could use, along with angling the sides in a bit if the trailer is wider than your car.
Once you arrive at the camp site, you can remove the nose and stow it under the trailer or in the car if your air conditioner pops out the front or if the nose prohibits proper access to your tongue box. If your tongue is short and you need to back up into a tight spot you can remove the nose while parking (just make sure you don't back over it

)