My advice is to go for a canvas knapsack rather than a leather satchel (they're pretty common and easy enough to obtain if you know where to look). Other than that I'd say you're on the right sort of track, other than that, the only advice I have outfitwise is go for a pair of dark trousers and sturdy boots with shirt and braces (about as light as you'll find with most Steampunk outfits, unless you want to add a military tunic, and remember in this situation layers are your friend (I assume you're not planning on showing off for the fillies, too much
), gravel rash is NOT pleasant
(why do you think Bikers wear leather?).