Some or I should say a very few do a reasonable job such as Rebecca at Chinaesl but in general the rule is not if you are going to be shafted but how soon!

Yes, you are quite right, dealing with a school directly is gett ing more common.
The same applies for companies.
Some consultancies who are not specifically language mills or 'agents' can be OK.
Language mills, after school study centres are mostly charlatans.

You only have to check the classifieds to see the same jobs advertised over and over again...reasons

1)Job doesn't exist and the ad is a come on...for the agent to get your details so he/she can hawk them around prospective clients as one of their teachers.
2)The management are total A-holes and staff are constantly leaving.
3)They don't pay their staff and constantly employ FOBs so as to get 6 to 8 weeks unpaid lessons.
4)The money is total shite eg. rmb100/hr.One outfit is constantly advertising for a manager/programme director for a salary of 11,000/month

If you are qualified, experienced and working for less than 250/hr, unless there are fringe benefits eg apartment, etc. then you are a mug.

We all know the adage "pay peanuts get monkeys".
Well in China it also goes "get paid peanuts get treated like monkey"

I get nothing less than 250 an hour for 60 minutes and in some cases 300 for freelance and I have more offers than I have available hours. Depends on your age, experience, qualifications, presentation and expectations.

Teachers in China and whores, yes there are definite similarities.