So there seem to be only a few scenarios available.
1. "Trade LMA this summer for the boatload of young players/unprotected draft picks." CLE has already made it known that they'd trade the #1 for Kevin Love. If that's the starting point, I'd imagine you could pull some more assets away (#19, #31/33, SAC's protected 2014, future 1sts). And if (since?) LMA is that much better than Love, then you'd think you could get even more. That CLE wants LMA isn't a made-up rumor by Simmons. It was reported by Yahoo a week before Simmons talked about it.
As for people talking about having to pay a higher salary for the #1 pick, I don't think that's much of an issue. If you get the #1 pick, you're going to still be paying that player less than Wes, and only about 1.3M a year more than Freeland.
This seems to have the highest volatility, but highest ceiling. It's not close to the lowest floor, though.
2. "Trade LMA next summer or at the 2014-15 trade deadline for a significantly reduced amount/quality of young players/draft picks." This isn't the most horrible idea--seeing if you can make the 2013-14 team as competitive as possible and fulfilling LMA's wish of a big body. There are a couple of issues, though.
a) depending on your level of optimism, the return in the summer of 2014 for LMA will range from "significantly reduced from this year" to "rent-a-player". You're also cutting out a significant portion of suitors. This summer, there's a small chance that LMA wouldn't gripe about going to a team that has sucked but is seen as on the rise (CLE, SAC?, CHA?) in addition to the normal "contenders" like HOU, DAL, OKC, etc. Next year? I don't think there's any way that CLE/SAC/CHA/MIL/17 other non-contenders teams in the league offer much of anything in exchange for one year of LMA right before he takes money from a contender in the summer of 2015.
b) If you do manage to trade him in 2014, you're going to be left with Lillard, 2 more years of Batum, one more year of Wes, our bench, and whichever overpriced big body we bring in this summer (Jordan/Asik/Pekovic/McGee/whoever), the #10 pick, no pick in 2014 (1st or 2nd), whoever you can sign for the MLE in 2014 and the return from the trade.
3. "Don't trade LMA at all--he's an All-Star and there's NO WAY he'd leave Portland at the end of his contract. Get a 'defensive-minded center who might only play limited minutes' and build around LMA and Dame."
This one has both the lowest ceiling and the lowest floor. In what I see as the most likely scenario, we are decent next year (probably even a playoff team), lose our pick (leaving us with a total of zero picks) in a great draft, only have the MLE available to improve next summer, and use that single acquisition and personal growth to possibly make it to the 2nd round before LMA leaves for somewhere else for nothing. OR, assuming that he does stay, we're still with Dame/LMA/Batum in his final year/Leonard/Big Body C and our bench, with our 2015 MLE acquisitions and no way to improve going forward other than MLEs and mid-round picks. I don't know if I see that as a championship team.
Additionally, if you think that LMA is sticking around past 2015, then it seems like you're committing today to a 5-year max for him in the summer he turns 30. That's going to be at least a 5yr/95M deal that starts out at 16.5M and goes up to 21.5M when he's 34. Maybe he'll be worth it. Maybe he won't.