And please, don't tempt me! Steampunk is a style that I love and normally I'd like to do a Steampunk deck. It's just so worn out...
Then, sir, I present you with a CHALLENGE. Create a steampunk (or gearpunk, dieselpunk, pick-your-alternate-history-variant-punk, etc.) deck design that:
a) doesn't say the name of the genre ANYWHERE on the cards or the tuckbox (nor in the KS campaign, should you actually decide to produce it),
b) does NOT use gears in the design unless they're presented as working parts of an actual machine rather than ornaments, clothing accessories, wall hangings, etc., and
c) is absolutely gorgeous, a pleasure to look at and to use, a fantastic blend of form and function.
I believe that c) will be the easiest part... Think about it, it's what makes us so tired of seeing "steampunk everything" - the pretention, the gears where no gears belong, the implausibility of the settings and the people, etc. Make such a deck whose "story" could just as easily be described by the simple terms "Victorian" or "Old West" but with just a tiny science-fiction-y twist to it that would make Jules Verne or Herbert George Wells jealous, while at the same time seeming 100% plausible, the kind of story that could have been reality were it not for a tiny turn of events in a different direction.