One question which a person like you can reply I believe. Some people upvote their own post, is it legit or can have any bad impact in future? I know a person who has 5000+ SP and uses this to upvote his own posts only.
As long as one has enough voting power to support other people, it's okay to upvote own content once in a while, especially if it's great content. Own comments should only be upvoted for visibility reasons and I don't do that normally. If someone upvotes only oneself, it shows his lack of human behaviour and he might get flagged for that in future.