Not really. Selecting the party leaders from those elected to lower offices is how we elected senators until 1910. The founders would be hip with this form of indirect republicanism.
We had people complain that mccain got selected by non-republicans. opening up the party leader elections to primary voters runs that risk.
The Ill GOP is in such bad shape this cant hurt it too much, but dont assume this is a good change.
A better system would be to elect the precinct chairs and county chairs in primaries, and elect the state leaders at the state convention.
That is how the Texas GOP does it, and it works well.
After seeing further comments, I realize that this kick in the pants is probably what the Illinois GOP needs, to shake the status quo. OTOH, I dont think its the right precedent to use for other states.