Question particle

I've moved 'ku' to being one of the 'what' words, so I need another CV to act as Eo 'ĉu.'  But then I got to thinking about making it a little more versatile.  Let's say the word is 'xu.'  It could act just like Eo.

Xu zi fumspir fumkana?  Do you smoke a pipe?

Or, I could arrange for xu to make a question out of the following word, not the whole sentence.

Xu zi fumspir fumkana?  Do YOU smoke a pipe?  Is it you that smokes a pipe?

Zi xu fumspir fumkana?  Do you SMOKE a pipe? (as opposed to doing something else with it)

Zi xu fumspir xu fumkana?  Do you smoke a PIPE?  Is it a pipe that you smoke?

Problem with this is, how do I make the whole thing a question?  Well, 'ke' turns a whole phrase into an argument, thus.

Zi jino.  You are a man
Go jan ke zi jino.  I know that you're a man.

So, ke can operate with xu the same way.

Xuke zi fumspir fumkana?

I think that'll work, so the equivalent for ĉu is xuke.  Now, what about an afterthought?  Well, 'hay' means yes, or 'it is so.'  So:

Zi fumspir funkana, xu hay?  You smoke a pipe, don't you?

How does this sound to everybody?