My feelings have changed over the course of the season. I don't think Rants deserves the same salary as Mack, but with the rumors the salary cap jumping up significantly it changes things. If Rants is making $12.5 mil you can still ice a competitive roster if the salary cap is going to be $95-100 mil in the next few years.
If he wants more than $13 mil, I agree with the trade. Maybe Rants might've signed for under $13 mil in the 11th hour, but it's hard to pass up on a player like Necas to potentially re-sign Rants.
But it will ultimately depend on what they do with the extra cap space. If they get another impact player like Jones or Miller with the cap they're saving this year and next year i'll give it to CMac. But if all the trades fall through and we're left with just Necas and Drury, i'll be disappointed.