If anyone is having trouble conceptualizing the long-view on this, let me help clear up your confusion.
Doing that hypothetical trade would leave us with:
PG - Crawford/Walker
SG - Bradley
SF - Jeff Green
PF - Sully/Oly
C - Zeller/Biyombo/Fav
2014: Celtics 1st, Nets 1st, Bobcats 1st
2015: Celtics 1st, Clippers 1st
2016: Celtics 1st, Nets 1st
2017: Either Celtics or Nets 1st
2018: Celtics 1st, Nets 1st
#1 - You'd likely bottom out this year. There's about 7 guys in this draft who are likely franchise cornerstones. Draftexpress.com has Jabari Parker going 4th. For the sake of argument, let's say we drafted Jabari Parker.
#2 - Shocked at the dismissal of the Bobcats youngins. IF they played on Boston right now, these same fans dismissing them would say they were future superstars. Zeller and Biyombo are 21 years old. That's baby age. Biyombo was a #7 pick and is averaging 10 boards and 2 blocks per 36 minutes. Zeller was just the #4 pick in the draft and has played a total of 8 games.... he could pan out to be a serious NBA player. Walker is 23 and is a fine young asset who averaged 18, 6 and 2 last season. That's possibly way too much return for Rajon ROndo and our bad contracts.
#3 - You'd have 30 million dollars in cap space. That's enough to sign two max contracts. I don't think we'd sign LeBron James and Carmelo Anthony (both free agents), but it's theoretically possible.
#4 - You'd still have Jeff Green's meaty contract + boatloads of young players and draft picks that you could offer for the very first available superstar. We'd have more young assets than any team in the league... this is the Daryl Morey approach.
#5 - Not sure on this one, but would we still have Paul Pierce's trade exception?
Bottom line: Theoretically within a 8 months you could have:
Jabari Parker - franchise player
Max contract #1
Max contract #2
Superstar
... and plenty of remaining young players to fill in the gaps. At least a couple of which will pan out to be starters or stars in their own right.
Literally the only negative is losing Rondo. I actually think the Bobcats are giving up too much, but I'm someone who admittedly sees Rondo as a Top 10 PG in a league loaded with PGs... He's not a superstar. It's a small sacrifice for a rebuilding franchise.