Here is a stippling picture I found... It is very time consuming but if you are really desperate about wanting screentones then you can just put the dots yourself... (This isn't done by any pro that I know of because of the amount of time it takes to stipple)
I've done this many times before traditionally , so I'm very good at it . The monstrous downside to that is like you've said it , unfathomable time consuming process ... which is why I don't use it when doing a long-term projects .
I'd usually just generate/create the screentone template myself (Digitally , not traditionally . Don't have the resourse for them) . Time consuming , yes , but at least I can easily adjust it to fit the picture's need without having to re-create it again & again . So , I'd agree with the point that it's not worth buying a new software if you're using it only for the screentones as you can make one yourself , both traditionally & digitally (I made mine with Photoshop) .