Very well done and I understand why you have nominated it! Very good jokes and I haven't spotted any sections with no humor. Something which you can add:
As your article is called "The Last King of Scotland", you could also say something about the movie.
How did Britain react to Bonnie after he got defeated and exiled.
Whether or not he provoked any rise of Scottish patriots.
These are just suggestions and I did not find any defects.
I liked the article very much and your concept of glorifying and making fun of Scots and Bonnie is very good! You explained everything well and the humor coexists with the history. The fact that you named the article after a movie but talked about Bonnie is also funny. However,
You talk about his son bit I did not find anything about him elsewhere. Has he really existed? If not, than it has to be explained why you talk about this fictitious person. I know that Bonnie had a daughter and if the son did not really exist, a question of sex and strange appearance could be raised again.
At the beginning of the article you recite Bonnie's adventure with the woman bishop on the roof. There is no more reference to this particular event but you say at the end that Bonnie was to allowed to become a bishop. If there is a connection between the two, you can talk more about that and make it clearer, maybe in the "Early Life" part.
There is a problem with the encyclopediness (which I have mentioned in the "Prose" part of the review): you tell a story and if your article can actually be considered an UnBook. I don't know if you want to do anything about this.
Prose and formatting:
Nice job but a Proofreading service won't do any harm. Concerning the encyclopediness, there is a lot of story-telling and of your personal opinion as well as your national honour. Knowing the subject of your article, I don't know if you want to change this and I leave this choice for you.
Meanwhile, here is my small proofreading (I will tell you about several grammar mistakes which I often cannot correct myself because I don't know how you want the sentences to look like; all the mistakes are very small):
On Wikipedia, it is "Jacobite pretender" without a capital letter in the second word.
In the section "Return to Scotland" I am not sure if "arrived on his new capital" is correct.
In the next paragraph you wrote: "For some reason however...". Another order of the words will probably be better.
On the text the "Maxim gun" has a capital letter and in the image caption it doesn't. Further in the section the word "maxims" is also without a capital letter.
In the second paragraph of the "Battel of Culloden", the sentence: "Bonnie was ready however on the next day to fight," has a wrong order of the words.
In the same paragraph the word "fight" is repeated twice. As there are three sentences only, the repetition is not very good there.
The sentence which begins with "Bonnie hoped" and the next one with "it was also hoped" do not go well together because the verb is the same but in the first there is the Active and in the second one the Passive voice. I don't know if it is against grammar but it does not sound well.
One of your section titles is "Conspiracy Theories..." and there all the words start with a capital letter. It is the opposite in another section: "The Continuation of the claim...".
Otherwise, I have not noticed anything else.
Very good but the last parts, if illustrated, would have an even better humor and effect on the reader. You can add a picture connected to Scots running away, something about Bonnie's wife, etc. Try to choose something that will look true and historic but then destroy this impression with the proper caption.
I really like your second picture and the caption is also very good!
The first one is also very good but the comment could be even better (or not, this is how you decide). Instead of using a simple rhetoric question, there could be something a bit more complicated. For example, "Bonnie's access to the throne has almost been refused because of his physical appearance". This is just an example to show you what I mean but you can write what ever you would like to.
Average score. I don't have much to add except for the fact that this is one of texts that do not annoy you with all that Wikipedia stuff (templates, etc.).
Very good article! To sum up, there is not much to do about humor, on the contrary to formatting. You concept is great and I understand that this article has been written by a real Scot!