So glad to have found this thread, I love autumn in every way - especially the clothes! Lots of great ideas on this thread already and I've enjoyed looking at the suggestions and dreaming of cooler days and wrapping myself up cosy and warm.
I've created myself a list, if anyone has suggestions on any of these I'd be very grateful:
A wool coat - I completely failed to find the right one last year. I think a slightly fit and flare style would suit me best. I'm 5'1" and belted styles look like a dressing gown on me, anything too unstructured looks like a sack (which is annoying as I love both those styles on other people). Preferably grey or navy, definitely not black.
A leather jacket - biker style, again grey or navy and suitable for short arms! All the ones I've tried on have sleeves that completely cover my hands and would be difficult to get shortened due to zips.
DM boots - though @BagelGoesWalking I love the ones you linked to so may stomp around with you in those!
I already have a leather skirt which I bought in the sale last year. I haven't really worn it yet and need to work out how to style it, but I love it and can't wait to wear it 
For those of you looking for brown boots, I have the dune Bertie boots (the ones with the buttons) in brown. They're more a dark tan than chestnut. I love them (though they may be too fussy for some people's style)