You can jump up your score by doing good in IELTS exams and getting your bachelors & masters assessment...If you know french, it can boost up your score.
It is really difficult to say what the maximum score can be as it is based on number of factors. More the merrier
Try and push the score north of 400 somehow - maybe by improving IELTS scores to at least 8 in Listening and 7 in other sections, learning French and adding those points etc.
Even landing a provincial nomination seems difficult with a below 400 score but look at individual PN threads on the forum to see if any of those can help.