Intermediate at zulrah, how do I improve kill speed/kills per trip?

I have 303 KC at Zulrah, so I like to think I'm decent but I'm not particularly good. My kill time is typically between 2:00 and 2:30, only going above if I splash an extraordinary amount. I usually only get 1-2 kill trips, getting a 2 kill trip about half of the time, it depends how hard the Blue phase smashes my face in.

I can't figure out if upgrading gear, or leveling my stats would be better for me, if I need to level range/mage which one should I do first and with what method? I'm actually kind of poor, especially after the zulrah nerf it's hard for me to make 1m/h.

Here's a recording of a typical run https://streamable.com/9kyd6 I tried to get a 1 trip but couldn't stop getting 2 trips until I turned the recording off you can mute the music, I forgot it would record that. please note that I have full Ahrims armor and toxic trident now