Just my thoughts but... I have built a few furniture pieces that were commissioned. Each of these were from photos and wood selections made by the client. These projects took twice as long to complete and I stressed over therojects more than any others I have ever completed. I have realized that his was because it was not my style and my heart was not in it! I do this because I enjoy it, not for the money so I decided that from now on I will only build things I enjoy. If I complete the project and do not like the finished product or more importantly if my wife does not like it I either sell it or donate it to a charity for their benefit.
I beleve you should build what you like. If you want a door made of box elder, build it, enjoy the process, enjoy the finished product etc. You can preserve the color by either using a transient red dye painted over the cooled sections (the color of the red with a little stain can match the color very well). You also have the option to finish the door with a finish with uv protectant. This will hold the natural color for many years. If you use a hard finish on the surface coat, it will not be as soft. Also it will still be harder than most of the hollow core doors with a thin mdf surface. In addition if you spend a lot of time on the design details, the door will always be beautiful.
Build it because you love it. Worst case if after a few years you are unhappy, you can build another one and use the current for firewood. worst case, you have several hours invested, $200-300 in lumber invested that you can repurpose and the enjoyment of building what you like.
In 2013 I purchased a quarter sawn sycamore slab with the intention of building a maloof low back settee with a natural edge. After about 75 Hours, I had a piece sanded and ready for finish. Aesthetically, I did not like the piece. I took it in the house for my wife's opinion and her exact words were "it's ugly". I went back to the shop with the thoughts I could cut the upper section of the legs, the arms and back rest off with the thoughts it could be a coffee table. That did not work either. I did not give up, I turned 22 spindles, cut a crest rail and made the piece into a Nakashima style bench. I finished the piece. My wife still did not like it primarily as it was not her taste. It did win best in show at the 2013 NC State fair so someone liked it. I placed it in a gallery and sold the piece for $1800. I had $150 invested and about 200 hours so after commissions made less than minimum wage but I enjoyed the challenge, won a ribbon at state fair and used the cash yo buy more lumber for another project. I grew more as a woodworker and as an artisan with this project than with any other project I have done. Overall I would do it again but will never build a comission of someone else's vision!
this is my 2 cents