I've seen older videos and screenshots of RealUI showing that there were arrows above and below the hp/power bars (for player & target) that would move in relation to how full or empty they were.
Were those removed? I'm partially color blind, so catching the health levels changing from black to red is hard to notice out of the corner of my eye. Is there a way to add those arrows back in, or am I totally missing something?
Arrows were removed in ver 8. You could try oUF_Real as a standalone Unit Frame replacement.
Can disable the default RealUI unit frames through: /realadv > HuD > Unit Frames > untick Enabled
Some things are anchored to the RealUI unit frames, so they'll need to be adjusted. Can't recall all off the top of my head, but:
/realadv > Frame Mover > look for Raven frames anchored to unit frames*
*To find the frame names of the new unit frames, type /fstack and mouse over a unit frame.