Bad idea? Tell that to the guys playing banjo and reso. They do it every day on strings MUCH thinner and more delicate than yours. Besides, the real concern should be the tone. Metal picks will be clanky and bright. Celluloid will be less clanky and will have that aggressive pick attack, but nowhere near the strength of attack you get from a flat pick, because you will never get a fingerpick that is as strong or heavy as a good HEAVY pick. According to what I have read, Robbbie Merrill uses this technique exclusively and he uses clear plastic ones.
I use a 2.0 mm Dunlop Tortex that I carve a crosshatch pattern into with the tip of a knife blade. The picks stand up to the most demanding punishment, they have a solid attack, and they are thick enough to hold the carved crosshatch pattern (so it won't slip around in between my fingers). Celluloid won't stand up to my playing, so if I play with finger picks, it has to be metal.
Also, consider that metal picks can be bent and adjusted to fit comfortably, while celluloid can't.
Bottom line - learn to use a flat pick and you won't have to look for ways to fake it. If you insist on faking it, you have to be willing to compromise and experiment.