[SuzushinaYuriko]

Code Geass is a shoe-in if you want a protagonist similar to Light.

Steins;Gate. Okabe may act silly and proclaim himself as a mad scientist most of the time, but he's an excellent protagonist with a serious side.

Kamisama no Memochou has one who starts off relatively normal and increases in maturity throughout the series.

Maybe you should give Baccano! a try. There actually isn't a specific main character for this show, but the person closest to one (Firo) is pretty badass. This anime is confusing at first because it jumps around in time, but the story and characters are some of the best I've seen.

fate/zero is an excellent one. However, this is also a series with a pretty big cast so it doesn't always focus on Kiritsugu.

Nodame Cantabile is an excellent romantic comedy series that takes place in college.

Chuunibyou Demo Koi ga Shitai! was also pretty enjoyable. It starts off as comedy and gradually turns into a romance. The protagonist looks wimpy, but he actually isn't dense. It's not a harem at all, despite the amount of girls in this show.