You said you want a yellowish green hue, something around 90°. And you said you don't want a color that' s too bright. This leads to this official, current color: #86BE43. IMHO, this doesn't look so good. This 90° hue is half-yellow half-green, so it's one of the brightest colors, and thus it needs to be heavily subdued. But then it just doesn't look so good.
I suggest moving to a much higher hue, somewhere around 160°. This works better. And this is much closer to the cultural definition of a mint color.
You said you want a yellowish green hue, something around 90°. And you said you don't want a color that' s too bright. This leads to this official, current color: #86BE43. IMHO, this doesn't look so good. This 90° hue is half-yellow half-green, so it's one of the brightest colors, and thus it needs to be heavily subdued. But then it just doesn't look so good.
I suggest moving to a much higher hue, somewhere around 160°. This works better. And this is much closer to the cultural definition of a mint color.