I wonder how many conditional sentences' types are possible. Basically, there four main and two mixed types. By mixing tenses, it could be up to nine of them. Are the rest viable? I came across the following examples in 'Full Spate Pre-Profficiency Primer':

• After you have just sold alcohol to a young guy. If he is if under eighteen, you should not have sold him the alcohol.

• If he promised to bring the drinks, he will.

• If you will take a seat, the doctor will see you shortly. (Likely, the former will demonstrates politeness only.)

• I would be grateful if you would tell me a little about your friends. (The same politeness, but would instead.)

• If he will keep eating all those biscuits, he can not expect to stay as slim as he used to be.

I would be grateful if someone could shed more light on the topic.

This stuff is closely related to distribution of a grammar between Vantage\Advance\Proficiency (B2\C1\C2) buckets. The goal I am striving for is to ameliorate the command of English. In the view of being new to this site, would it be wise to ask more questions in this topic? I would love to gain more grasp on the grammar at advanced\pro level and the second question is to get community's take on about aforementioned primer. What materials could be recommended besides?