Stats with current gear and level don't have much impact as with i130 at level 50. You can say it's comparable with i90 at level 50.

Doesn't mean you can't optimise if you wish.

Spellspeed right now has a small effect on HoTs. But as one stance doesn't use HoTs at all, spell speed isn't as valuable compared to piety, crit and det.
In a nutshell; you can't go wrong with piety and determination. Crit would potentially be better than spellspeed as both stances benefit from it, unlike Spellspeed - for all you Nocturnal sect haters, let's forget about personal opinions about the sect for this particular topic.

Tldr; piety/det >>> crit >> spellspeed