While making this mod I learned a lot about GUI modding and realised that there are so, so many cool things possible! Many of which I can't really implement myself at this point because they're require a quite different fundamental layout of the planet viewer. It'd mean restarting really, and I just don't have the time. But I want to write them just to inspire other people and encourage anyone else to make their own planet view (or other GUI) mod maybe with some of these things included if they like, or using the ideas as a springboard for any of their own stuff.

Ethics Variations
One really cool thing possible would have been to re-theme the UI based on the ethics of the controlling empire. So for example if we're looking at a planet held by slavers there could be shackles and chains and other grim looking art elements draped over the planet view, or whatever. Agrarian Idyl colonies might have a nice natural theme. And so on. It's technically very doable, and even I think art is not too tricky to handle: The art provided for the empire rooms already in stellaris already cover a great deal of personalities and empire types and could totally be re-used in different ways. A modder could also quite simply overlay that room art wholesale in front of the city view to create the same effect we get on empire creation or diplomatic screens. The specifics aren't too important, I just think it's great that the entire thing could be re-themed like this. (Infact, the entire UI like the topbar and outliner could get the same treatment!).

Army icon animations
I could have turned the army icons into simple spritesheets that displayed fun little animations. Like a gun firing, or a soldier walking, or a tank rolling on it's treads, stuff like that. It's also possible to do more fancy things with army health bars. In vanilla they are literally reusing the fleet combat health-bar. I changed it slightly in my mod (resized) but instead of a simple red ring it would also have been possible to have an animation where the army icon slowly breaks apart as it takes damage, or gets splotched with red blood until it's entirely covered! It's all possible, if you get the art for it.

More Stats
I could have added far more flavour stats. Does this planet have a 24 hour day? 20 hours? 40 hours? How long is a year? What kind of seasons do they have? What season is it currently? How old is the actual world itself? (Not just the age of the colony). All this could have been assigned and displayed. I didn't want to "clutter" the UI in my mod so I held off, but it could all also easily be neatly moved behind a small scrollable element (like I have with my districts). Also setting everything up for earth/mars/etc wasn't something I wanted to spend the time looking into.

It also occurs to me that more stats wouldn't necessarily need UI space. The tooltip presented when mousing over planet class could include lots of extra flavour details for no screen space cost at all.

Current Events
A similar concept to the above. There could have been an area on the layout assigned purely for a block of text which changes every X years. The block of text gives a short 1-3 sentence description of a current event on the planet, news-reel style. Some people went missing in the mountains here. A new species of bird was just discovered here. A magnitude 9 earthquake struck the west coast. A bomb threat on this penal colony. A plague in this city. And so on. this was also cut due to layout and, again, time. It's basically a separate mod (it'd be a lot of stories for me to write.)

Planet Size
One thing I really miss about the old tile system was how you could tell at a glance whether you were looking at a small moon or an epic gaia just by how much was on the UI. It was fantastic! Sadly the mod I've released here still doesn't really fix that, though I tried to make the world size icon bigger/more prominent. If I were going back to the drawing board I'd look more into this, possibly unlocking full new sections of the panel as planet size goes up. Not sure on this to be honest but I think there is something there.

Surface View
Another area of the UI could have displayed a ground map of the surface, so you get a sense of the continents. This isn't actually as crazy as it sounds because the model texture assigned to the planet itself already looks, basically, like a map of the surface! You could just call it in the gui. You could also maybe shunt it off onto the planetary features side panel or something (at the top, before the features list)

More Ecology-Style Elements In a Dedicated area
By the time I got to adding my ecology element I was really struggling to find a place to put it on the UI. I kind of wish I had left a chunky gap beneath the city view but above the building views because this would have meant I could have had a either 1. a really nice wide ecology icon (like the event art ui) or 2. space for LOTs of different square ones, representing different things. And, again, with a bit of scrolling this UI area probably wouldn't have needed much room to fit.

There could have been flavourful icons for dominant weathers, seperate ecologies for flora AND fauna perhaps (brain fungus, anyone?), and whatever else.

Cities:
Let's talk about capital cities. I'm interested in the mods on the workshop that have given multiple variants of your capital building based on your ethics. How about a UI element that does that instead. This doesn't have to affect gameplay at all. So for example if we're spiritualists we get some gothic beautiful ecclesiastical church-city. Instead of squeezing that idea into a small building icon, it can be it's own entire element. And then we can pull from the empires namelist to actually NAME the capital city of this world. When we click around the galaxy we're seeing all these cool capital cities! On top of this I especially like the idea of being able to assign the capital city to a specific planetary feature. This would give us a great sense of where people are actually living. For example a capital city at the Rich Mountain deposit. Or a city in the tropical swamp. Even blockers, maybe? A volcano city. when I watch/read sci-fi there is nearly always a declaration of where colonists are actually hanging out (in a valley or whatever) and Stellaris just doesn't cover it. Realistically this could be it's own mod, with small potency improvements to the planetary feature you picked or something.

Residents:
What about an art box that shows some prominent alien NPC/resident living on that planet? An exile from X country (garak anyone) or some-such. A refuge related to the refugee event you just got. How about moving my colony_type emblem down to this UI area so it doesn't obscure the city_view so much. In-fact, were I starting from scratch, I would have designed those emblems very differently to take full advantage of the space.


So those are just some mad ideas that occurred to me as time went on and anyone could make. Hope it was a fun or interesting read!

To hide the blurriness, you could use some sort of filter like scanlines or something, at least until you get high-res art.

@LNSS
Thanks for the idea! there are already scan lines on it, however, hah!

could you add tiles for crisis worlds like Infested worlds? they showed up in the lategame and it's super wierd to not have any art despite being in the base game