It's hard to change subjective personal impressions, but an objective assessment of the law and order situation in Taichung would be that it's "continuing to improve." You can't just casually overlook the hard work and achievements of the police.
雖然主觀的個人印象不容易改變，但說台中治安「持續改善中」，應該是一個客觀的描述，員警的努力和功勞不能輕易抹煞。