I'm going to sound biased, but Perfect Fighter. You can make it fight anything and people/the admins on rsbotting.com even create presets that have any monster really. It's a great bot and it's one of the ones that I haven't regretted buying.
Although PerfFighter can be adjusted for pretty much ever combat area in Runescape, unlike the AutoFighterPro where you'd have to buy a bot for Rock Crabs, Fire Giants, etc.
I haven't botted combat states in a very long time, so I can't give you an answer on that. Last time I botted was when nobody knew how good the Ghouls were near Canafis lol, I got so many levels there .
I botted in places where people struggled to get to, like the Fire Giants which are on the journey to Steel and Iron dragons (entrance in Karamja by paying some tribal dude, I forgot the name, you then need a hatchet to cut through some roots). I'd suggest wandering around there and finding a quiet spot, you'd need B2P tabs as well.
Lolz at hobogoblins. Little homeless goblins hehe.
Anyways I've gained quite a few levels at ghouls as well. Nowadays there are 2-3 people there so I would steer clear. I think there are some lesser demons on karamaja somewhere that most f2p people train on but it's empty on members worlds. Then again you can't use b2p tabs on lessers.