Gizmo,
Mercury can't even form an exact aspect with the Sun except a conjunction. It can't even form a semi-square, since it only gets a maximum distance of 28 degrees away from the Sun, and usually it doesn't get that far.
With Venus it's similar, but Venus gets about 47 degrees away, at maximum, though usually getting closer to 45 degrees away. With Venus and the Sun a semi-square becomes important because it can only form a semi-square, a semi-sextile and a conjunction. Sun semi-square Mercury is at least a very interesting aspect. If you think about Mercury and Venus this way, and how they are more or less "chained to the Sun" (because they have to stay close), you may want to think about this in the future.
Now, I would pay attention to aspect patterns. Supposing, for instance, you have two planets almost exactly opposite in a chart (they need to be this way for what I'm about to describe to happen), and two planets are both semi-square to one of them. Then those planets are sesquiquadrate or 135 degrees away from the other end. It's almost like having a weird, different kind of yod—and containing an opposition.
If your chart is full of major aspects to a planet, and many of these aspects connect personal planets or outers to personal, you may choose to look only at those. It's a lot to take in. However, what happens when a planet makes no major aspect to the other planets, or when an outer only makes major aspects to other outers?
If you use Chiron, asteroids, fixed stars (and so on), you will find some aspects from Uranus to other planets (such as an opposition to Chiron). But if you only use the Sun through Pluto, then Uranus is sort of hanging around in your 4th. And not really touch any other planet.
So in this case you might want to think about Uranus/Jupiter, and you might check here:
http://www.skyscript.co.uk/uranusaspects.html
To get a feel for how this cookbook page describes the relationship of Jupiter to Uranus, first check the trine and sextile for an idea how the planets might work together. Then read the conjunction, square and opposition for the difficulties. Don't take any one paragraph to literally. Notice how the author attempts to keep the same basic principles but adapts them to ease or friction and the principles of the different aspects (conjunction is right there, but sometimes like the "nose on your face", opposition stares are you "from across the room", square is presenting you with something that you can't see because it is "around the corner". I'd say the 135 degrees is subtler, but even harder to see.
I would think of such keywords as: unorthdox, expansive, liberty, and so on. Think of the minor irritation of the aspect, note that the signs of the planets are nor harmonious, and so on.
Now try the same thing with Neptune and the Sun.
http://www.skyscript.co.uk/neptuneaspects.html
Read the positive and negative aspects for Sun/Neptune. Try to pick up the concepts behind the thumbnails. A difficult Sun/Neptune aspect will heighten sensitivity, add to shyness, increase the need for down-time/rest and so on. It's good for imagination, for compassion, empathy and so on, but the hard aspects literally make it "harder" to live with the sensitivity. The problem is that Sun in the 12th does many of the same things.
Then think of these odd aspects as mostly "flavoring" to the chart.
Final note: the Jupiter/Uranus aspect is nearly 2 degrees, rather wide for such a minor aspect, and separating, and these are both slow moving planets. The aspect was about dead-on 10 days earlier, which is pretty general, in the charts of people for more than 15 days. But the Sun/Neptune aspect was only there for about 4 days, more personal, but still affecting a lot of people around the world.
When it gets REALLY personal is in a case like my wife's chart. She has Moon/Saturn square, with Mercury sesquiqradrate BOTH of them. She is one of the most intelligent people I've ever known, but very shy.
