Whether you use Google Keyboard or you’re using your phone incorrectly, the keyboard app has been updated to version 5.something (rolling out slowly, or download the apk from the source link below,) and adds full support of Unicode 9, a one handed mode, adjustable keyboard height, and bunches of other fun stuffs.
One of the most useful options I’ve found so far is the ability to delete a suggestion by long pressing it.
Android Police covered it better than I have time for today other than missing that you can use the spacebar as an arrow key (swipe left/right,) so rather than rehashing, I’ll just post a screenshot and direct you to their piece.
The APKs are available for download, and carry the Google signature so if you’re upgrading from an earlier version they’re signed/you know they haven’t been tampered with.
If you’re not trusting of that, just wait a few days and it will be live in the play store.