I agree nearly wholeheartedly with your assessment.
Their weakness is youth and guard play this year. With both big guys coming back next year and Edwards, Stephens and Davis at the wing and SG positions, they should be very good everywhere but the 1 spot. And, mostly bc I just don't follow Purdue that much I can't recall if Octeus is just a one yr transfer or like a Zeisloft 2 yr guy. If Octeus is gone, they'll still have a sore spot at that PG position which will limit their success. If he returns or somehow they shore that spot up I could see them as a top 3 team in the league next year.
I don't like Purdue, but I'm not such a homer that I won't give credit where it's due. Painter has assembled a pretty nice team that could go on a run next year. But, the real question for them is can Painter put multiple good classes together. He's been unable to do that in his time there and as a result has suffered very poor seasons every few years. The class of Etwaan, Hummel, etc was great but when they left they had $ hit.
All in all, I'm a big Painter supporter. He'll give them something to cheer about(top 3-4 finish) every handful of years but mostly will never recruit well or consistent enough to make much noise. CMP is like Peter in the movie 'Office Space'. He does just enough to not get fired. It's a perfect fit.