First, I suggest you try to use terminfo to properly ensure your terminal supports the "main subset" you've mentioned. Second, I suggest you get in contact wit

First, I suggest you try to use terminfo to properly ensure your terminal supports the "main subset" you've mentioned. Second, I suggest you get in contact with Thomas E. Dickey, the maintainer of libncurses and terminfo, to see how he tests that library - on something like 15 different platforms. Finally, over time, consider relaxing your set of terminal requirements - either with workarounds or with limitation of functionality for less-capable terminals.