Ok. So Mr. Taxman has given me a generous amount back this year for my tax. In turn SWMBO has given me permission to purchase one piece of camera gear.

my options are;
Canon 430exII speedlite
or
I can save for a couple of months and get a Tamron 10-24mm

I don't exactly have a "preference" or "style" on what i shoot, at the moment i'm just enjoying learning. Taking note of my existing equipment (see sig), what would you recommend be my next purchase? feel free to explain why as well.

Thanks in advance!