I would go with the first one. It's not quite as simple as making a bot class because you have to make sure that every steamcommunity function acted on each bot in parallel, which would obviously be difficult to do with that amount of bots (you might be able to create separate steamcommunity instances though I'm not very familiar with this).
Also if you're running that many bots you will need to use proxies to avoid rate limits otherwise you will get screwed fast.
