The size of the triangles themselves really aren't important at all (as a matter of fact, you can turn them off entirely while still keeping them functional -- that's what I do so the visual appearance is better while I don't lose any functionality.)
So, what I assume you're asking for is a larger "tap area" so they're easy to hit. We'll consider this in our future development -- so long as you understand that it'll make it harder to hit links such as strongs numbers, translation notes, etc. if those items are in or near a corner of the screen. |