Best niches for List Building?

Hello Guys,

I just started with List building and target two different niches(no mmo) I have a High quality squeezepage but, I get no optins ans only a bit traffic.
Maybe because my niches are to targeted or simply not good.

So my questions are:
How you select/find a niche that could be good for List Building?

Do you give them a freebie?

Any suggestions for free traffic in the beginning ?

Thanks

i think bizop or workathome since people always need and uses money in that niche