Stream is a very convenient way of getting posts and comments, but it's lacking. Streams only return 25-50 or so comments, which may seem like a lot until you realize you're looking in all the subverses. If a bot is working on only one subverse, this is next to nothing. Especially if the subverse is not particularly active compared to the others.
I have two suggestions on how to solve this problem:
The Voat way: Include a stream per subverse. This way streams are properly utilized and can get up to 50 posts/comments on a subverse. Which is ideal, since 50 comments in 30 minutes is plenty enough.
The Reddit way: Include something like Reddit's /r/subreddit/comments/.json, which will return ALL new comments on that subreddit (up to a certain limit)
The advantage of the first way is that it saves Voat bandwidth, just like the regular streams. Maybe even more (Putt?).
The advantage of the second way is that it gets comments that were made before the bot launched.