So I'm the "team" that designed it the first time (with input from others, of course, but it wasn't designed by a committee or anything), and the primary goal was to enable a single-click install for the majority of users, biased towards simplicity for users who are less-experienced at administering a Windows PC. This was balanced with the fact that many users would already have 2.7 or 3.4 installed, and those installers had some poor, and irreversible, design flaws.

These flaws forced us to install py.exe for all users by default, otherwise the majority of people would end up installing it lower on PATH and would never get the updates. As a result, it would break, because the launcher included with 3.4 wouldn't reliably detect 3.5, and we didn't have any option to detect or upgrade it.

However, this meant that admin permissions would be required for a default install, which is not acceptable. So the front page option to switch that setting was added so that non-admin users could easily disable the admin requirement.

The PATH option was added under protest, because too many users/teachers rely on it for their coursework and wanted it to be easier to find. If we could safely enable it by default we would, but it's fundamentally an unsafe operation. But it's popular, so that's why it's on the front page.

So unsurprisingly, I like your variant A the best, which is really just tweaking the Tools/msi/bundle/Default.thm file a bit. It maintains the short path for those who want it (which we believe is the majority of users), and hopefully makes it clearer for advanced users.

I dislike variant C because of the second page for simple installs. And for variant D we wouldn't offer per-machine installs for the runtime, and we wouldn't offer PATH options for the launcher, so it basically boils down to making the advanced button harder to find with less explanation.

So if you'd like to propose a PR with changes to the files in Tools/msi/bundle to match your actual UIs, feel free. It _should_ automatically build the installer if you've modified those files, and you _should_ be able to download it for testing, though if not it isn't hard to build locally with Tools/msi/build.bat.

(And of course, this would only apply to 3.11, so I've updated the version field.)