My order is this:
1) Rondo for Howard. The least likely to happen as this a top 5 PG for a top 2 Center. It will take more than Rondo $$-wise and value wise to get Howard. I understand the Howard reluctance, but this move leaves makes us an immediate contender. May not work out, but my opinion is that you gamble when there is the chance to get a young dominant player. He is not Vin Baker.
2) Green/Lee for Smith. Though I am not a huge Smith fan, this provides us the best player in the deal and leaves KG and PP and a legit shot to do something significant in the playoffs this year or next.
3) KG for Bledsoe/Jordan. Step 1 to building future assets. 2 good young pieces add to a young talent pool that would now have Bradley, Sullinger, Bledsoe, Jordan, Rondo, Lee, Green and Melo. Hate to trade KG but would do this ahead of standing pat.
4) Trade Pierce. If you make the KG trade there is no reason to keep Pierce IF he brings back 2 additional assets -- perhaps a young talent and a pick. C's would jump-start the rebuild by 2 years (at least) by getting assets for KG and PP. I'd hate to trade Pierce but he will return much more now than at the end of year or next year.
5) Do nothing (add a scrap heap PG and big). As much as I love KG and Pierce, doing nothing is my least favorite strategy. This team as is, is so unlikely to win anything more than maybe a round in the playoffs in the next 2 years that no big moves is, to me, the most disappointing. I'd much rather start the re-build with the assets that KG and PP could return if we can't add a big talent to the current roster.