Right now the energy lights on most warframes end up looking like a mix of the primary and secondary colors, which not only looks terrible, but it also doesn't match the energy colors of armor, sigils and other attachments that use a single energy color.
Here's my Volt for example.
I had my energy colors set as blue and yellow. After the latest changes in Update 24.7 his emissives turned green, which doesn't match the armor's energy.
Same with Chroma.
Sometimes the energy colors aren't even consistent on the frames themselves. For example, Day and Night Equinox Prime have different energy colors, with the combined form having both.
Finally, the energy effects on some frames got messed up. Valkyr lost the pulsating effect on her face. Revenant's flares look way too bright.
No picture before the changes sadly, but it looked much better and the colors weren't getting mixed together like that.
In my opinion all energy effects should be reverted back to what they were like in Update 24.6. The energy lights should be determined only by the primary color, with the secondary only affecting abilities and special energy effects like the ones on Revenant, Ember and Nezha deluxe.