New Darius is BAD

I played new Darius first time today, and I have to say that he is BAD. His Q, which was his main trading instrument, requires .75 seconds to charge, meaning you cant do extra auto attacks in between your skills. You just get outraded if your enemy dives past minions onto you even if you land your q. Moreover, the biggest problem is that its WEAKER, except if you build AD. The problem here is, if youre behind, you can no longer go tanky Darius and last in lane. You're pretty much forced to build AD if you want to do any damage, but that doesnt work if you fall behind, say by a riven that has teleport and does jungle. You cant outrade the Riven with you mediocre damage Q, and the lack of auto attacks from charging that Q.