I agree with you about the natural game... I havent been doing this for too long, but I think that just saying what you are actually thinking and not something that you are trying to remember comes across a lot better and doesnt look as 'robotic'...

On the other hand when I just open a set and start having a friendly chat, I seem to get carried away with just talking. Quite a few times now I would open a set and get a conversation going, but I would not escalate or try and close or I would miss IOIs or opportunities to tease the girls a little bit, and would realise that only when I have left the set. That could be because I'v had a bit too much to drink or just lack of practice.

So, in conclusion . . . ) Canned material is ok if you are a bit nervous, but if opening is not that much of a problem then just say what comes to your head. But, its good to rememeber that each interaction with a girl/group should lead towards something - social proof, number/kiss/fuck close etc and to have the 'structure' in mind.