The article has to satisfy a search criteria (More to follow). Views will be determined by the article ranking in the Search Engine Result Page (SERP) and the randomness of someone attracted by the article title and the summary shown. In other words, they must see the title and read the short content shown. From there it is based on interest and impulse to open the link.
To help with a high ranking there are Search Engine Optimization (SEO) techniques based upon principals. Two basic ones are the title itself and keywords or phrases. The keywords should be in the title, the summary, the opening paragraph, and in the article in a natural manner. DO NOT keyword stuff an article or use it too much. Article quality is another. For more I suggest researching the Web or asking in the forums.
Yes, the ranking of a website helps the article ranking in the Search Engine Result Page (SERP). So, that said, an article at the niche site has a better probability of receiving views over the main site HubPages. The Niche sites have a higher ranking since they are Niche content sites and not general content, which the HubPages main site is.
To get an idea of how well an article is ranked is to search the web using a question that the title and article answers. That is how a user does it. For instance with your article 'Top Ten Historical Warrior Factions' I did a search; 'historical warrior factions'. It is listed on the first page at #6. But, if I search 'Warrior factions' it is on the 8th page of the SERP's at #8. So, seen it is dependent on how someone searches for information that they are interested in.
Next, the user will assess if the title answers their quest for information. They will read the seen article summary or first paragraph opening. Notice that the keywords will be in bold in that. For instance, that article used above the seen information reads:
"Centuries pass and wars are fought, among the groups of soldiers we sometimes receive a more savage or powerful warrior. Here is a list of ..."
If the title and that short content attracts the user, then they will open the article. Notice the keyword warrior appears, but historical and faction does not. Perhaps rewrite that sentence with all the keywords might help?
I hope that helps give an idea of how it works . . .
Based on what I have heard in the forums article acceptance can be from a few days to a few weeks. It is dependent on the workload of the editors reviewing the articles. Other than that I have no other information as I have only submitted a few. I did get a notice within a week.