Nothing really to add, except good luck! I started a canopy for my 46g a couple years back. I was actually pretty proud of the design, but when the front piece didn't bend as perfectly as I wanted (okay...so I'm a bit of a perfectionist!!), I lost steam, and now it sits about 85% complete. I'm sure very few would even notice...but it bugged me.
I'm not much of a wood-worker, but I do like the idea of the slotted wood, assuming you have the tools to do the multiple slots (I'm assuming you are talking top to bottom). That might actually help the wood bend the way you want it to and give it a more uniform curve.
Please do post some photos if you get something you like.
46g bf, XP3 w/ vertical spray bar, CO2 w/ SMS122 & diffuser,100% Flourite, 96w+55w cf AHS, AGA Member