The character development is standard, when they actually do it. The issue is there's no fucking plot because the heroes not only outnumber the villains 100:1, but they're generally stronger too. Not to mention UA is just the Ivy League for heroes so literally everyone is some super attractive preppy kid with a bright future. What's the point? Deku doesn't even get hurt when he fights now, a necessary step but it took away what little conflict existed.
The actual concept is fine, but there's no real intimidating threat and the villains are aimless. The only reason conflict exists at all is because of surprise attacks, otherwise everything it totally fine all the time.