Michael, have you tried checking out the 'Help' on the app? - I'm assuming you are referring to the app. It's available under 'Settings'.

I noticed (android) that when you switch maps OSM/etc you are taken to your current GPS location instead of the area ou were looking at

Yes, that seems to be what CT does when we choose a map from the extended menu. 

I wonder is there a way of displaying altitude and gain while planning a route on android. It seems like such an obvious feature that maybe I'm just not seeing how to display it

It's available. Simply place your thumb on the 'travel info' at the bottom of the screen and flip it up. 

However, I'd see the app as a 'quick'n'dirty' planner. The website is far superior in terms of features and clarity - for me at least. It is entirely possible to create highly detailed routes using the website on your phone. Your first issue of zooming to 'home' disappears, for example, on the website.