The difference is not easy to see but:
When the top of the 5 ends in a 45° angle it's a pointed 5, if the angle is about half of that, it's a blunt 5.
When the A of regina points to the left side of a bead, it's small beads, if the A points to the right side of a bead, it's large beads.
So your pictures:
1. correct
2. in my opinion blunt 5
3. large beads
4. correct
The arrows are identical. You see, the first two are definitely blunt, the last one definitely pointed.
The 3rd one is a bit tricky, but I would say also blunt. The blunt 5 is much more common than the pointed 5, especially the large beads, pointed 5 is difficult.
But at least you have a pointed 5, I don't have any yet.
The beads is no problem when you know where to look for. And you don't have to look how big the beads are, but where the A points too. There is no discussion about that. It would be much more difficult if you had to compare the size of the beads. Then you indeed go nuts after looking at many coins.
The pointed/blunt 5 is much more difficult because the difference is so little. I can easily believe you went nuts after looking at over 100 coins. I had the same problem with the Australia 1 cent 1966 with the blunted or not whiskers. After looking at tens and tens of these I went a bit nuts too. So I've put them aside and will have a look at them later on.
Like I told you, when you know where to look for concerning the small/large beads, you can determine it in a blink of an eye without any doubt. All your beads in A, B and C are correct.
The 5's are a much bigger problem. The blunt 5's in B and C are correct.
Here are the 5's from A and the first one of B:
The one from B is definitely blunt 5, like you thought too.
For A I would say: the second one definitely blunt, the third one pointed but the top isn't too clear on the picture to be 100 % sure.
And the first one:
The top of the 5 isn't clear either. You can see an elevation between the green arrows. I don't know what it is, but it looks like it isn't a part of the 5. In that case, the top of the 5 isn't visible which makes it very hard to say if it's blunt or pointed.