brimforge said:

There is always room for more(!) bounty hunters, why should there be only one or two

This greatly depends on the story itself, I guess, if one or several are needed. And there is such a thing as too much (more on that later) ;)

see ESB, there were in fact nearly 10, ok not all had much screentime, but I think if one finds guys with well designed costumes, additional scenes can be inserted for a more logical plot ...

Right, but there was one who stood out more than the rest in ESB and that was Boba Fett, because he had the most screen time. Of course there could be some other bounty hunters in the PT as background/secondary characters, but my suggestion was there needs to be a main, cool bounty hunter of the PT (a non-Mandalorian to either replace most of or all of Jango - and Cad Bane is a good pick), just as Boba became the main, cool bounty hunter for the OT. The main villains, just like the main heroes, need sufficient screen time too so their character may be fleshed out and become memorable - but if you start to have too many main characters/bounty hunters, it detracts from this.