Rencently, I use TabNine with Company-mode to complete words and short sentence in Org-mode. And it provide me a very good experice, maybe you can try it and enjoy it.
my integration is as below:
;; The free version of TabNine is good enough,
;; and below code is recommended that TabNine not always
;; prompt me to purchase a paid version in a large project.
(defadvice company-echo-show (around disable-tabnine-upgrade-message activate)
(let ((company-message-func (ad-get-arg 0)))
(when (and company-message-func
(stringp (funcall company-message-func)))
(unless (string-match "The free version of TabNine only indexes up to" (funcall company-message-func))
(add-to-list 'company-backends #'company-tabnine)