Hi there J,
(1) I have not built in a specific ZOOM feature into the Fan Chart app itself mostly because most browsers have their own built-in method for doing that. On my Mac computers, for example, I use COMMAND + to zoom in, and then COMMAND - to zoom out, and that works in any browser I'm using - Chrome, Safari, Firefox. (COMMAND key held down then press the + or - keys). Windows does the same thing, using a different key instead of COMMAND). On my iPad or iPhone, you can just pinch to zoom in and out. Hope that helps.
(2) If you Colour by Country you get very distinct colours to use, and just yesterday, I added a feature to allow you to customize the colours by country if you wanted.
When you switch to Colour by Birthplace, I have it programmed to look at the Country colour, then choose a random shade of that specific colour, so that all places from Canada, for example, will be some shade of red, so that you can see the big picture of by country along with the varying degrees of movement within that country.
Alas, some of those distinctions are very slight and some work better than others. That is certainly one area that I agree could use some improvements - but my sense of colour (depending on the shade) is not always up to the task, so, if you are volunteering to help me with that (and any others here with a keen sense of colour) - that would be great!
- Greg