Before trying to tackle bots one would need to ask the right questions beforehand and discuss this maybe with some folks who have some developing background to get at least an idea what could be a possible way to get this problem "solved".

This is usually the issue with topics like these: developers (like me) are saying that there is no 100% way to determine who's a bot, that it would ultimately result in witch-hunts and that many bots/software-solutions would go undetected (thus punishing the honest players), but then non-developers come around and argue: "I don't care, find a way".

The real solution IMO would be something like:

1. Give players more data so that they can compete with bots using statistics
2. Reduce the amount of time required to battle (20 games per day only on ranked is a lot). This is also a similar issue to voting on hive: who has time to vote 10-20 times per day (hence curation trails => bots)