I was jumping in to toss a vote for the Sig 226/228 based off of your original post.
Based off of the post I quoted above, it isn?t sexy and doesn?t meet the criteria of your original post but a Glock 19 is hard to beat for practically and definitely slots somewhere between your 17 and the shield.
If you insist on a metal frame CZ might have some options for you as well. I like my Sigs but they are chunky pigs and I don?t really like to carry them.