You're asking me to explain to you why the contradiction I've given doesn't fit the EA diagram??
No, I'm trying to get you to understand that what you're saying is
internally inconsistent.
Forget UA for a moment. Just consider light. Any given part of a light source will emit light in all possible directions. I have no idea why you think this would be any different with EA, but it isn't. The diagram doesn't suggest that different parts of the Sun emits light in different directions, but simply spaces the vectors out so they can still be visible. You could just as well have them all coming out of the same point of origin.
Carry on forgetting about UA for a moment. Let's look at the red lines you've drawn. Remember, we're looking at something where you decided the initial angle, but its initial speed and the acceleration it's subjected to is set in stone. We can easily illustrate this problem as a much simpler (and, to an extent, analogous) classical mechanics issue.
To explain why what you're saying is nonsense, let's do exactly that. Here's a very simple physics problem, a cannonball is shot at a certain angle and speed, air resistance is ignored, and we only consider how far it will go before it falls.
Pay attention to the shape of the curve. Now, compare it to what you propose for an angle of 45 degrees in an analogous situation. Notice how your light ray doesn't curve at all? That's analogous to the cannonball magically zooming away into space. Or compare it to the one ray I highlighted for you earlier - in which the cannonball goes backwards and upwards, like some crazy boomerang.
The issue here isn't that you don't understand EA, but that you are completely lost as to what a constant upward acceleration would look like in
any context.
The rays of light starting from the sun, are they more like the first picture (emenating from the centre) or the second picture (essentially random in all directions).
Neither accurately describes how light sources behave, regardless of whether you want to consider EA, FE or RE. That said, rabinoz is correct in that the bottom diagram is slightly less wrong.