I feared this was someone just trying to spam us with links to their youtube videos. I'm glad it has turned into a discussion
Back to the videos...
The problem is that if someone understands any of what you're showing and they spot the errors then they will wonder at the accuracy of the stuff they don't understand.
My suggestions:
Around 0:30 - I would be a little more accurate about valence electrons. Whilst what you say is true, is is misleading. Sure it has 4 valence electrons and it wants to pair with another 4, but it's not because it has 4 electrons that it wants 4 more. The idea is that the shell will be full with 8 electrons, so it can fill up to 8.
Around 0:57, I would make the other doping agents an "OR" rather than a "But...". To my mind it seems that the "but" implies some sort of difference or inferiority.
I would also mention which one is a P and which is an N dopant here (but not explain it until later). This is an important concept which seems to remain obscured too long in this video.
1:37 - you mention free electrons (which are obvious) and holes (which are less so), then refer to N and P type layers without explicitly saying which is which. I could be left asking "Is the layer that had the extra electron N, or the layer that gained it?" and "Is the hole what was filled by the migrating electron, or the place the electron came from?" An "N" and a "P" appearing over the layers, and a better representation of the hole might help.
3:00 "No matter how high the voltage..." could be "At normal operating voltages". This would tell the same truth, AND make people realise that other stuff can happen at higher voltages.
Also the pink later is graduated from top to bottom. Does this graduation mean anything? Is it the strength of the doping? or is it just to make the picture look nice? Since the meaning in this image is explained by the colours, a use of colour could be expected to mean something. If you do wish to use a graduation (or a difference in colour saturation) then shouldn't the emitter be darker? At least if it's correct then people can come back later and think "well look at that -- it even hinted at a deeper truth". People who understand will probably pick up on it and have their confidence increased. And then one could discuss the base doping...
I also wish I could see the edges of the N and P layers under that blue
3:18 You show the collector current as equal to the base current (count the electrons)
This explanation also seems to be at odds with the "at any voltage". This is especially true as the base is always shown as being +ve. Perhaps if it were initially -ve and was changed to positive?
I'm not overly sure of the exact physics at this point, but I (as explained above) don't trust what I see. Perhaps I would be expecting to see a change in the electric field somewhere.
3:55 You describe the bulb as being one which automatically turns on as light intesity falls. This is a description of the circuit, not of the bulb.
As described previously, placing the load in the collector circuit is really essential. Otherwise you'll be teaching exactly the wrong thing, and worse, describing a circuit that doesn't work the way you say it does (you're not wanting to introduce feedback at this stage)
4:10 Absolutely wrong. most of the current cannot flow to the collector when the transistor is off. Also it adds to the bad assumption that people make about current being supplied by a voltage source (as opposed to being determined by the load).
As also previously mentioned an AA or other 1.5V looking cell is not the best choice.
If this is the case with the LDR illuminated then surely the line should show current flowing through the LDR rather than through the base.
Also, you've just switched from electron flow to conventional current. The ways the arrows point is exactly the opposite of what was seen in the last animation. This would have to cause confusion.
Frankly, I'd probably create a circuit that turns on the light when the LDR is illuminated because that (whilst less useful) is a far easier explanation that doesn't directly invoke questions about the BE voltage required to turn on the transistor.
In any case, as 4:36 you add an extra arrow showing current exiting the emitter and going through the bulb. It looks as if current has been pouring into this transistor and can now escape. Not a good analogy. I would have preferred to see an arrow drawn first showing base current and a small emitter current, then a larger (fatter) arrow showing the collector (and hence emitter) current.
At present it is actually hard for me to pick the bits that are not going to be contradicted later.