Simmons is damaged goods, but even in that state, he plugs in some really important stuff to a team.
In the end, can you pay a guy $37M or $40M if he can't play at the end of games? That's tough, but he would make us a defensive monster, he'd speed us up in transition, he'd add a ton of passing skill, and he'd rebound. We'd still have Langford and Nesmith. We'd still have Robert Williams, Al, and Moses Brown up front. We would be OK with a bigger guard that could just spot 3's and play defense. We might even be able to start Nesmith, because Simmons and Al are that good at passing.
My main concern is he can't play at the end of games. But we would be a very tough team to beat, especially if Nesmith and Langford evolved. It would probably be worth the risk, even if Simmons can't fix anything. And if he could just become a competent foul shooter, whoah!