I have a hard time believing that Ivey can't be developed into a decent press Corner.
He's long and has great size.
I was blessed to have an outstanding DB coach working with me at Deerfield.
I watched him turn a mediocre WR into one of the top CB's in South Florida in one year. Kid went from completely unknown, to locking up everybody in the Dade/Broward All Star game, to earning a D1 offer. (mainly off of reputation)
He didn't run that well, but the kid was long (6'1") and had a dog mentality. The rest was developed by his DB coach.
That length, along with the techniques taught by his DB coach, allowed him disrupt much faster WR's before they even got into their route. (i.e. Nathaniel Joseph - rendered him useless and a non factor on the outside)
But this goes back to KNOWING WHAT PERSONNEL YOU HAVE and ADJUSTING YOUR SCHEME ACCORDINGLY.
I played press and press-bail like 80% of the season because I knew I had big physical CB's that were hard to get around.
WR's want to run routes unimpeded, they don't like being disrupted. It's extremely hard to stem your route when the CB guarding you is 6'1"-6'2" with long a$$ arms and decent feet. The WR has to go AROUND HIM before he can get his route going. This disrupts WR/route spacing and can also throw off the timing of the play.
If you got big a$$ Corners like Blades, Stevenson, Ivey, etc...then IMO your coverage scheme should be based on disruption on the outside.
You can play a "match" version of Cover-3 (my preference) or you can play Press-Quarters.
Steele brings SEC experience so I'm hoping that he's the type of implement some of these concepts.
The key is THE COACHING AND TECHNIQUE at Corner though.
If the CB's are whiffing and letting WR's run by them and get into their route, then it defeats the purpose of playing press. The idea is to bully the WR within the first 5 yards. That takes good eyes, good feet/lateral movement and good technique.