What can I do to make my simple hooks more comfortable?
Pencil grips work! If they don't fit because your crochet hook is too thin, you can wrap your hook handle with tape (masking tape is easy to remove) or paper (but you have to use glue then) up to the thumb rest (the flat part in the middle of most hooks).
And if you want something permanent you can use polymer clay, I believe that is cheaper than sugru.