Thanks again for all the great advice, folks. I'll try to address each in turn.
Jennifer, your advice to keep an open mind (others have alluded to it as well), is something I'm trying very hard to work on, and perhaps making gradual progress. ;-) I read through that link that Sharon put up about traptents and dogs, and I am more open to that idea now. That said, a thought that did occur to me about 4 season tents like the Unna and Akto, is that I know first hand how very warm they are. I have winter camped in a Hilleberg and the inner tent felt an easy 15-20* warmer than even the vestibule. I could probably drop the weight of my sleep system by a good pound using a Hilleberg, which would help offset the pound or so heavier that they are than other shelter options, while still retaining their bomb-proof benefits. As Peter even mentioned, down might be more likely for me to try out with a bombproof shelter. Still, I'm going to follow your advice and not rule anything out.
John, I noticed that even the lightest bear canister out there (the Bearikade Scout, I believe), is barely lighter than my BV450, and incredibly expensive. That may be one area that I am better off eating the bullet on the extra 4 oz or so and saving a couple hundred dollars, since I already have the BV450.
Several people have mentioned clothing already, so I'll address it. I'm sure I'm a bit heavier than most, but not outrageous, like I used to be in the clothing regard. What I took on my last summer backpacking 3 dayer in the Sierras was a frog toggs UL rain jacket (no rain pants, I figured if it was unbearable I'd set up my tent anyways), balaclava, Arcteryx Bravo softshell jacket, felt Akubra hat, smartwool lightweight wool longjohns (top and bottom), and 1 extra pair of socks and skivvies. Obviously that doesn't include the stuff worn constantly, like my 511 pants, long sleeve REI nylon shirt, etc. That amount of gear worked fine for me, both while hiking, sleeping at night, and even during several thundershowers. As I said, I can probably save some weight in this area as well, but at least nothing was outrageous or excess (in my opinion anyways). I used to pack two pairs of gloves, Gore-Tex ECWCS parka and pants, etc. I've downsized a ton in the clothing area already.
Peter, could you clarify one point you made about the Unna vs Akto? You mentioned "go faster" with the Akto. Are you simply referring to the weight being a pound lighter, or set-up, takedown, etc? I was surprised by this comment, because that is why I chose the Unna over the Akto. The Unna, with just two poles (stakes almost optional), it is probably the fastest/ simplest tent I've ever set up. The Akto (never seen one in person) only has one pole, but WAY more staking/ guying out hassle it looks like. You've owned both, so I'm happy to take your word for it, but could you explain it a little more to me?
Thanks again everyone. I'm sorry, I know I'm missing some of the good comments to reply to, but there is a lot of good info I'm absorbing.