ALL your questions might be relevant to FB maybe, but not to Steem. Have you seen any rules here? There are no rules, only things that people agreed that are good to be flagged, that's all. Steem has lots of bots, created by simple users like you or me.
Always remember that it's blockchain, so everything you do can be seen by anyone who wants. Here are the records of every single action made by your account, for example: https://steemd.com/@a4illusionist
every single action
Multiple account upvotes? well, if you invest to their Steem Power, you're actually making Steeem a better place to be. Until you recieve the confirmation e-mail for the new account - everything you do is considered ok
Now let's sum it up: 1. You are free to do here anything you want. 2. Everyone is free to do anything they want, so if some random idiot flags your post - nobody can help you. If you flag someone for no reason - nobody but you can remove the flag 3. Steem has no laws, only reccomendations. 4. The purpose of you creating 1 account or 1000 accounts - it's your own purpose, nobody has the right to blame you. 5. You mostly won't be flagged for adequate polite actions and posts (no guarantee though)
So, everything is solely up to you