If i had lots of SP I would join you in flagging, but at present I feel it is best to use my minimal SP to upvote worthy content. I will leave the flagging (downvoting) to those who have higher SP and investment.
I am not too sure how flagging the bots will go, many have huge SP, so you could be asking for a huge retaliation war, but I wish you the best in your action against useless comments/spam and bots.