Even though those are some good cards, they are too slow in the current meta, or you don't have the cards to make them useful. Plus you have to remember the actual limitations of the bot. I remember when patron warrior was a thing, it was too much work for the bot to do without roping out and also took a fair amount of planning ahead so it just wasn't a good fit for botting even though it was the best deck at the time.
There is a 100 gold limit every day for ranked/casual/tavern brawl wins. You could have your bot run exclusively on ladder at rank 20 to farm golden hero portraits at the same time. The bot is very unlikely to hit legend with the current card pool. The last time it was close was when secret paladin was a thing so don't worry about that. If you really want the monthly rewards, rank 5 is the highest you need to go and you can check out this post for help with that.
http://www.hearthranger....7491_Project-Rank-5.aspxArena rewards are unlimited but arena is notoriously hard right now, for humans and bots so I wouldn't waste your money/gold.
As for maximum bot potential; it's getting you 100 gold a day (the max, and and also much more than most people earn) so it is at its maximum potential. Even if you made stronger decks or the bot included stronger cards, you would still get the same amount of rewards, just in a shorter time. So if you're the kind of person who just sets it and forgets it, why bother trying to speed things up if it's working already?
I personally have two separate accounts (no real reason to) so once the bot gets 100 gold on one account I stop it and login to my other account then start the bot again. Depending on the winrate of the deck, this can take 3-6 hours per account so I need to speed things up so I can use my toaster laptop for other things too. I use a tool called Hearth Recovery that starts the bot every time the server resets (2 in the morning for me) and by the time I wake up, the first account is done and I manually switch accounts and get things going again. I know that HearthRanger itself can do this but I prefer Hearth Recovery because it opens up my deck tracker, HearthRanger, Silverfish, and even restarts all of that if the game crashes.
That's a lot of info and should give you plenty to go off of but let me know if you need more help