Welcome @Katherine! I know how you feel, I was so excited when I found SVS (a couple of months ago now) and it feels like just the right place because we are all into similar things, and all trying to make our journey towards better art 
And it's so much better when you can share and chat about it!
Your sketch is really cute, I agree with @Sarah-LuAnn that pushing the steampunk side would be better. I like the idea of hat and/or goggles, another idea would be to give him/her a monocle? That way you could keep the big cute eyes and even the lens effect could make one eye bigger, might make it look more quirky too? Also I think, as the brief specifically mentioned time-traveller then having some sort of timepiece would be good - clocks are such a steampunk thing, would really help fulfil the brief. Perhaps he could have a pocket watch which is connected to the trumpet thing, and the trumpet thing connected to the seat thing? (that way emphasise the time aspect and make it look like a time machine)
Also..thinking again about the hat idea, how about a top hat? - that's a common one, and often with steampunk hats they have goggles perched on the rim which again wouldn't obscure the cute eyes. Looking forward to see how this develops!