However, I wonder if devs like 343i actually add new servers to their games, whenever new ones are available? I could also imagine that some of these are not meant to be used for game servers.
Awesome response time you've got there mate. Titanfall at launch had Aussie servers down as low 18-25ms. Customs in H5 feel like that for the most part.
One word of warning I've found that ping Azure test website to be a bit higher than in game. The reason is Azure is configured as a web service by default and hops many ISPs for traffic etc. During internet browsing the difference between 100ms-200ms response isn't much given downloads videos etc. Gaming is quite different in its priority routing of direct XBL games traffic for example. Even my Aussie Vic Azure says 98-110ms on that site. In customs or when we actually get that dedis close to me in game it's more like 20-50ms. If people want it next week I can open up some networking tools and do a how to guide to actually test some things around Azure and dedis for your latency/traffic etc. Just remember when you're using terms like Azure you're talking web apps/sites for the most part, not gaming.
I really don't understand MS or 343 not giving us dedis choice or world wide match as a toggle. It's a simple toggle and selection list, Azure devs could code the crap out of that quite quickly IMO. It's by design/development from MS or 343 to not give that to us. The weird part to me is say they responded with it's to keep population pools across playlists globally, that doesn't fly with me. Perhaps initially on game launch but my gut tells me you give players the default setting and the toggle to select DCs, their in game experience is going to be that much better when they try toggles. If the casuals or those who don't care to try settings in games don't change it MS/343 haven't lost anything really. Surely the faster higher quality gameplay is what retains players. Titanfall still matches games today with an even smaller population than H4/5.
To address the quote snip above 343 or other game devs don't add servers to Azure. It's completely run by MS and they have containers of expansion with servers ready to deploy, have spare space in the datacentre they build etc. It's a massive network to rival any cloud provider. Amazon Web Services (AWS) is comparable to Azure for example, less worldwide regional presence than Azure. I don't know of another DC solutions company with such regional spread e.g. Australia has 2 Azure DCs and only 1 AWS. Same goes for the next closest competitor.