Not ever transfer comes in right away as a star player. Bru McCoy improved. Hendon improved. Milton improved. Many said the same about Dont'e Thornton early last year and now he looks poised to be a Top WR in the country.
We tend to have pretty high expectations for these highly regarded transfers but they aren't finished products and they have to adjust to new schemes, new settings, new demands, etc. Some transition quickly, some need a couple games under their belts, some need a whole season and offseason.
Staes has two years of eligibility. Kitselman is older and came in as a more polished blocker. He's clearly carved out his role to play. Ethan Davis is a more polished pass catcher. That leaves Staes as the 2 behind both in either situation. But it also means he's probably more versatile and he will be called upon when someone gets banged up.
If all that is true, I'd expect Staes to breakout either late in the season or next year.