So... A post is new, it has one other "zero-rated" answer, post an answer yourself, vote down another answer, you get prime real estate... That smells like a conflict of interest.

Well, one of the reasons downvoting an answer costing one reputation is to prevent the Slowest Cheater In The East effect. That is Stack Exchange's remedy against what you're describing, and it's working quite well so far.

On the other hand, upvoting competing answers is actively encouraged; there's even a badge for it.

As for voting on the question, I usually vote up any question I've answered^*. Any question good enough to be answered is good enough to be upvoted. From time to time, you see featured posts on per-site metas with a similar call; questions get voted on less than answers, in general. Preventing answerers from voting would be a step in the wrong direction, if you ask me.

^{*: unfortunately for you, feature requests and discussions I disagree with are the exception...}

So... A post is new, it has one other "zero-rated" answer, post an answer yourself, vote down another answer, you get prime real estate... That smells like a conflict of interest.

Well, one of the reasons downvoting an answer costing one reputation is to prevent the Slowest Cheater In The East effect. That is Stack Exchange's remedy against what you're describing, and it's working quite well so far.

On the other hand, upvoting competing answers is actively encouraged; there's even a badge for it.

As for voting on the question, I usually vote up any question I've answered^*. Any question good enough to be answered is good enough to be upvoted. From time to time, you see featured posts on per-site metas with a similar call; questions get voted on less than answers, in general. Preventing answerers from voting would be a step in the wrong direction, if you ask me.

^{*: unfortunately for you, feature requests and discussions I disagree with are the exception... Why? Voting is different on Meta.}