There are two things to discuss here:
1. Insta concede against X, Y, Z class
2. Concede back to rank 20 once rank X is reached.
You would be surprised how many times people insta concede. There are lot's of people farming golden portraits. They concede all the time - to avoid unfavorable matchups to get back to rank 20, etc. When I look in bot logs I often see that around rank 19-18 there are many wins because opponent insta conceded. It's even funny because many times when I derank bot manually to get him back to rank 20 I get free wins because other people are also deranking them and I always wait 3-5 seconds before conceding because of that.
I was really surprised by amount of people that gave me free win. Having that in mind I personally do not see insta concede option as a security threat because that's what many people do.
But OP was asking about auto deranking back to rank 20. That's another option and I would also like to see that option implemented. It was asked many times on the board. A lot of people do that already but they have to do it manually and it's really annoying. If you run bot you want to turn it on and check on him after 5-10 hours not after one hour to see if he's rank is not to high.
You want to sell people multiple licences. I can derank my one account, that's not that big deal (it's still annoying) but if I were to run like 3-5 accounts at one time that would be a real pain in the ass to check on them and derank manually.
Both options are just options - you can just implement a checkbox to use them - if someone wants to use them - let them have it. If someone is worried about security he do not have to turn it on. You can have both groups of people happy with a simple checkbox.
Hanker - yes you said already that we can make that in API, the problem is that most of us don't know shit about C# and how to use that API. And even if we knew we don't have time for that. People use bot to save time not to spend it on developing custom decks. Some people will develop this decks and thank god for them but as far as I can see we only have one custom deck atm.
Also there is this thing that main competitor to HSB has that options implemented from what I've heard. Let people decide what options they want to run but give them this options.
To sum it up:
1. Yes to insta concede against class X, Y, etc. - many people do it already manually, you can always add some random delay to make it look more human like.
2. Yes to derank back to rank 20 as soon as rank X is reached (would be nice to give people freedom to choose what rank they want to reach).
3. Give people options and freedom of decision - some will use them, some will not - all will be happy.
BTW two other threads about that:
https://www.thebuddyforum.com/heart...dea-future-insta-concede-against-x-class.html
https://www.thebuddyforum.com/hearthbuddy-forum/163478-request-concede-back-rank-20-a.html