A: If you haven't already try going to
Settings>Accessibility>Display & Text Size and play around with the options in there to see if they help you with the sizing of the interface.
B: Go to
Settings>General>Keyboard>Text Replacement and you can click the + in the upper right to define a new text replacement. I, for example, have one set called 'em1' that gets replaced with '
myemail@address.com'. You can set it up so that you can type whatever you like and it will auto-replace with "Please avoid sending a text, phones work better, and email never fails."
Also, maybe it's time to consider switching to Android as its interface might work better for you.