At 21, the reforms, and simple real-world budgeting Walker and the GOP has really boosted WI's position.
Four things are still holding it back.
1. As a traditionally blue/purple state, no one is yet willing to believe the change is permanent. Instead of pressing the advantage, the WI GOP seems content to wait (or hope) the dissolution of the public unions continues to cause the Left to just "take their ball and go home" etc.
2. While there's no oil here, the state's remaining heavy industry revolves around mining, drilling, supporting fracking, all things which the larger Federal government is actively hostile towards, and new mines in Northern WI which the state's current democrat minority has still managed to hurt/stop, despite these being largely "union jobs". Superficial environmentalism as a cover for what is mainly a desire to try and keep "anything good" from happening under Walker or the GOP majority.
3. Like a lot of states WI is more dependent on the health of the U.S. job economy as a whole, and not as able to drive job growth and a more independent internal economy like Texas has. To a degree, no matter how much the state government improves, we're at the mercy of the larger Obama/Democrat "jobless recovery".
4. High taxes. WI is still in the top 5-10 states for total tax burden. Despite the reforms, some individual municipalities school boards are still packed with liberals and union-friendly people aren't taking advantage of them. And as usual for the Right once it's in power, the GOP and even Walker seem to be turning timid and afraid to rock the boat after the whole reform fight and recall attempt.
What WI has accomplished over the past three years is amazing, by way of analogy, akin to the Moon Landings, but like the Moon Landings, there could have been more, and follow up.