I consider a client a regular when he is consistent with his generosity and scheduling. My locals may see me once or twice a month but my out-of-towners may see me every 4 months or so. A regular to me has seen me at least 5 times.
I find that twice a week visitors don't last in the long run. Afterall, I'd rather have a slow steady and consistent income rather than damn near rape your bank account to the point in which you freak out and never see me (and give me more money) again.
The extras I will give depend on his generosity ($$ + gifts).
Generally that entails phone calls, texts, sexy photos (all just to say hi, etc).
Sometimes I will cook for him (travelers love that) and if he is extremely generous I will buy him a very nice gift or create a little piece of artwork for him.
It's all management though. I appreciate my regulars and I want to keep them around.

Damn, look at all this free game I'm giving out.