Let's say Millsap plays 36+ minutes a game the next three seasons, averages about 19-20 points, 9-10 rebounds, 3-4 assists, 2 steals, and a block, all with good efficiency and unrelenting hustle. You're saying you don't want that? It's a waste of time and resources, a setback?
Not of it's going to impact our future cap flexibility to the point where that signing might come back to bite us on the backside.
The entire big-3 era we had clear holes in our team, but we couldn't fill those holes because we were crippled by the significant contracts of our stars. I could totally live with that though, because every one of those three guys was a superstar calibre player - as was Rondo in the last couple of years of that era.
I don't have problems overpaying and threatening future cap flexibility if it brings us either:
a) A player who is a legit two-way superstar right now (e.g. CP3, Anthony Davis, DMC, Russell Westbrook)
b) A player who is young, with potential to become a future two-way superstar (e.g. Paul George, Jimmy Butler, Andrew Wiggins, Kawhi Leonard)
c) A guy who can consistently (an completely) dominate games with defense (e.g. Serge Ibaka, DeAndre Jordan)
d) A guy who can consistently (an completely) dominate games with offense (e.g. Steph Curry, Kyrie Irving, Lemarcus Aldridge, Carmelo Anthony)
Millsap has never fallen in to any of the above categories and it's likely he never will.
He's one of those guys that desperate teams sign to max contracts as a backup plan when none of the real max contract guys want to sign with them. Kind like Josh Smith and Greg Monroe, except those guys had/have youth and potential on their side then they signed/sign their new contracts so that added perceived future value. Plus youth also helps with the contact numbers.
Unlike those guys Milsap doesn't have potential or youth on his side - low risk, low reward. His age also means that the max contact will be higher than a Josh Smith / Greg Monroe max contract.
Paul Millsap, as far as power forwards go, is among the best 2 way players in the game. Well, not the best, he's not Anthony Davis. But, he plays both sides of the ball at an above average level. Millsap might not be a max guy, but he's spitting distance.
I get what you're saying, but then you could also argue that about Angre Iguodala (among SF's) or Josh Smith (at the PF spot) a couple of years back, or Andre Miller back in his prime.
But nobody was taking Iggy over Carmelo, or Josh Smith over Blake Griffin, or Andre Miller over Tony Parker.
I guess what I'm trying to say is that Above Average Offense + Above Average Defense doesn't really = Elite superstar. More like 'good starter' or 'excellent starter' depending on exactly how above average those abilities are.
The way I see it depth, teamwork and all-round players make a team competitive, but it's those stars who dominate certain aspects of the game who separate a good playoff teams (or a great regular season teams) from the great playoff teams.
I believe that in the playoffs, the NBA at the end of the day is all about matchups - you see the same team up to 7 times and at least 4 times. You've scouted them as much as a team can scout and you know what they want to do before they do it - but just because you know what they are going to do, doesn't mean you can stop them from doing it.
This is where those elite players take over and can dominate an entire series, and often the opposing team, with all of their depth and versatility, just don't have enough sheer talent to stop them.
For example, lets say you're the Knicks at the end of a close playoff game (haha good one!

) and you have possession. You draw up a play, but that play falls apart - maybe one of your guys messes up a screen, or the defense reads and reacts, either way the play doesn't go to plan. You always know that if all else fails, you can get the ball to Melo and he will make something happen. Maybe he makes the shot, maybe he misses it, but the instant he touches that ball every single defender's eyes are on him, you'll probably see three defenders running at him, and either he makes the impossible shot (which he does so often) or he uses that distraction to find the open man in the corner for the game winning three.
Lets say you're the Clippers, and you're in a tied playoff game, you're on defense, and you're playing Cleveland in the finals. You try to deny Lebron the ball, but he finds a way to get it. You try your best to defend him, but he ends up blowing by the defender and finds an angle to the basket. Your main defensive play has failed, but you still have faith because you know you have DeAndre Jordan down there protecting the basket...and if Lebron is going to go for an easy layup his going to have to get it over that massive arm.
These, right here, are the guys you can depend on time after time to change then entire course of a game because they are do dominant at that one thing they do. When all of your team plans fail, you can depend on those amazing individual to put your entire team on their individual shoulders and say "coach, I got this".
Paul Millsap is not that guy. He's consistently good across pretty much every area of his game, but there is not one single aspect of his game that he's elite at. In fact nobody on the Hawks team is really that type of guy, and I think that's a big reason why they dominated the regular season so much, yet are really struggling to distance themselves in the playoffs.
Don't get me wrong I really like Millsap as a player, but it's pretty much certain that some team out there is going to overpay and offer him a max contract...so getting Millsap most likely means spending max money, and if that's what it takes to get him then I don't want us to go after him, because he's not worth that.