I'm using a font which comes with many AddOns. If you get Qusemap, I think the font is named Font1.
There is no way to detatch the power bar from the healthbar using ElvUI (which annoyed me at first too). At the moment I'm rolling with health and power bars together.
If it helps in any way... I am using the Pixel Perfect skin for ElvUI. I have a hunch that you're using the standard skin, which would most likely give results far from what you can see on my UI.
My unitframes are the default ElvUI ones, configured quite easily to look the way I have them.
Like Carebear said up there^ UI configuration can takes AGES. On this ElvUI edit, I spent more time than I'd like to admit teaching myself how to change things I wanted to change etc.
Carebear mentioned that he can spend months on a UI and then star tall over again (which can be seen in his UI gallery) which is similar to me also. I've been using the UI that I had before this ElvUI one for about a year now, but before that I would change it almost every week, just to get it right!
Just stick at it and you'll get there!
Regarding the unitframes issue: the actual unitframes are 214pixels wide, and 18high. The power bar is 3pixels high. The textures I'm using are named ElvUI Norm and I'm not actually sure where I got the font from... but it is a edit from the "Skurri" font. You can find the font in many other AddOns though, which I mentioned up there^. Also remember that I'm using the Pixel Perfect skin. (You can change the entire skin of the UI in the installation process when you first set up the UI.
(This should probably be in the "Sticky: Ask it! UI/Mods Edition" thread, but I am putting it here in reply to a post in this thread)
Hope this all helps!