If you're more into the supernatural and horror themes go for death note like what rotordave said but I want to add onto his point and say parasyte and hellsing:ultimate but since you are watching OPM consider watching my hero academia. If you want to watch the best time travel anime then watch steins;gate(it has a slow start but gets better trust me).

On another note I just re-watched Being John Malkovich for the first time in eons, geez I got bored after a while and cringed a fair bit but I did enjoy Fast 8 though