I would really like to reccomend Neo Ultra-Q to you guys. Each episode is it's own contained science fiction mystery, but they all feature the same three recurring cast members. It's a remake of the series that started the Ultra Series, which later evolved into Ultraman. But Ultra-Q and Ultraman turned out very different. It has a unique way of blending an aged look with a modern drama look, more mysterious or dark scenes looking like an old television program. Neo Ultra-Q features different stories than the original Ultra-Q, the latter I am actually still looking for a reliable way to watch.>>3328
I would reccomend Drive for something modern and well rounded (having a lot of drama but still being very shonen), W for something a bit more light hearted but still emotional, and Ryuki for something very dark and dramatic.
Also if you want to just watch some old pulp fiction style stuff with low budget practical effects see the original.
Overall, Kamen Riders "sister series" Super Sentai sticks to the old format more closely, only building up to a few major plot points per series.