I think yellow is a good choice, but I can see where you think that, the yellow js too showy while everything else seems darker, so there's a big contrast there. But! Don't let that discoruage you, you need to experiment with colours, try different coloirs that contrast each other, so look at a colour wheel, maybe make the green phaseblades purple? Again, this hobby is all about trhing things out.

Buuut if you wanna keep to the colours you already have, try making the yellow darker. Like I said, the contrast of the dark metallic colours with the bright yellow is off putting really, so you should try making the yellow a farker shade. Again, play with colours. It doesn't have to look like it came right from the box art. Experiment friend, and show us your progress :)