I am just self-taught freelance 3d render artist tbh, usually I don't do pixel art or GUI's and I never saw an art or digital design school from the inside but.. well I do freelance and so some work was in that direction even though not directly... and it is my hobby too ^^
And while it's nice to look at turning it into a game GUI would likely take some decent coder quite a while to do. In fact you'd likely have to code the GUI systems to transform values into percentages and then how those affect the image you are trying to blend in a position and stuff.... I think, that is the reason you don't see that many decent gui's around, it isn't exactly something you get working without a LOT of effort. And I mean hard, coding, effort.
And most of the really bad GUI comes from people just choosing really really bad names for stuff and generally ignoring how Information and color flows, bright colors in a gui are hotspots, thus if anything in your guy is bright in any way, it better be an important info (or guiding the eyes to relevant info). In Drox the GUI is glowing blue (I call it, the indy bright color blindness syndrome) because SOTS2 has the same problem... and it makes using the GUI extremely evil.
And second thing to do in GUI.
Information likes company@Bluddy (partially ,p)
That means, even though the % is not vital to be displayed displaying it in the same color as the descriptor and bar creates visual coherence and a "block", without the % value the information
would not be visually distinct to other information. And obviously my color choices just flow nicely because I am 25% red/green color blind, so you will NEVER see me use true 0,255,0 or 255,0,0 colors (RGB). ^^ the % would need to be done with whatever the in-game engine can do anyway so it could easily be made a toggle, however, I absolutely hate when a GUI does not give me information on first glance, and
mouse over is not first glance and impracticable in combat. As this GUI is a lot less bright than the default you wouldn't even notice the % unless you were explicitly looking at it. (obviously you are doing that now, because it is a mockup so you got nothing else to look at
The idea behind the % is by the way. Normal pattern of eye movement, first to name then bar then %, and you got instant visual feedback, you don't even need to read it, most humans understand the % scale without thinking about it. (often even to their detriment ,p) Yes, 50% health is very very relative. I know
But there is no way around that. Mouse Over should display the ACTUAL values though.
And lastly, as humans love patterns it just takes little effort in arranging information clusters /Shield/Energy fit together, as does AP (Armor Points) and HP (Health Points). It isn't exactly rocket science, and you can get that knowledge basically from just looking at how most decent AAA games make their GUI. Then just keep some basic symmetry and you can't fail.
But really, all a good GUI needs is a good font, a good layout and a good flow. It ain't rocket science, but when I look at most Indy games (AI War is a nice exception ,p) I get severe cringes. And then there is of course, that in-game the realities of most font renderers means that everything would need VERY careful formating and placing and a very decent font renderer to begin with, one that can do colors and opacity and blending effects, at the very least.
One of the only things this mockup does not tackle is how to keep the game background from flowing into the GUI. I would probably need to do some actual 75% opaque "underlay" of some kidn that sits beneath the GUI graphics and darkens everything behind it but does not fully hide it. Otherwise everything would have to be protected by full opaqueness.
Anyway, don't forget that it's easier to create mock-ups than it is to make that work in a game
This just was really fun to tackle because nobody ever asks me to prototype a GUI and I wanted to do it for a while now, well nobody asked me but the game GUI made me think "how can it look better" and that's usually leading to pretty images, at least most of the time