Just stop. Austin Nichols doesn't make up for losing all the guys ISU loses after this season. Long, McKay, Niang and Nader... If ISU landed this guy and Monte stayed AND ISU signed three other really good players then there probably would still be a drop off.
People have been saying this since Royce's season. We just don't know how it will shake out. Morris is probably at least 50/50 on staying. Him being without Niang could force him to become far more aggressive which might elevate his game.
We have no idea who Prohm will land between now and next year. A lot will depend on finding a transfer and/or a couple of juco's but landing Nicols (totally unlikely anyway), would go a long way to replacing some of what we lose.
What if Burton is a total stud? What if Ernst is better than advertised? What if Noskowiak + Thomas + Cooke next year can be just as good as Naz + Thomas + Cooke this year? What if we landed Arlando Cook and the Greek Freak 2.0 to go along with Nicols?
I know that's a lot of assumptions, but you're making the assumption that we won't land any additional players and our current players won't continue to get better.