Generally, I'd agree with this, but maybe not with a back up for Key. Key is so foul prone it's reasonable you'd get lots of minutes. Also, if it's a fairly young post and they're really good, it's also reasonable to think you'd actually begin to take Key's minutes by the end of the season. I may get slammed for this, and I think TK is a wonderful young lady, but if she isn't able to substantially up her overall game it's likely as a senior she'll start to give way to a younger player anyway.
So I say a fundamentally sound, culture good fit post with at least 2 years remaining who understands the role is what we need.