I was having a debate few hours ago with congolese workmates about that,so it inspired me this topic to know your views about it
as for me,i'd go with three atalakus,one tenorist and one more rough and agressive,and a third guy who is either a mix of both or has a or a unique voice

Since the evolution of congolese music from the mid 90s, groups with more than one atalaku have had more success than those with just one. Djuna Mumbafu succeeded as a single atalaku because Pepe Kalle and Empire Bakuba suceeded generally. variation of animations from two atalakus was and is still refreshing. So for me one is too monotonous. Two or more is welcome. Thanks to Fally, you can now use 100 atalakus (exaggerating here) on the same song. That is refreshing but limits the animations to maybe one or two at the most.

 The Bill/Celeo, Brigade/Bebe Kero, era pretty much was the format for most bands around that time.

Two Falsetto and two Tenorist, creativity and competition hold more value in this department.

Personally,  i would prefer to have 6 or so atalukus but making them work in pairs on songs/sebenes so that each generique and sebene has completely different animation. I find it monotonous when the animation is the same throughout an album. I think if they worked as am saying, many artists and albums would be successful because there would be a greater choice for listeners to pick from so for instance you wouldn't end up with just one good animation like ''Ya Mado'' repeated several times. It would also bring competition amongst the atalukus.

3, one falsetto, one tenore and the third one can be a mix of both like how Kasangidi is or another tenor.

Two......caludji/ekokota....bill/celeo fomat....

I think 1 atalaku is enough. I don't like ones that have more, for me it makes the show inconsistent. There are exceptios, however. Bebe and Marius in Zaiko Famila Dei complemented each other very well.

I'll go with 2...maximum 3.like we had
Just like Nono/Bebe   Nono/Adoula Bebe/Marius ekokota/Caludji Caludji/Genta  and QL atalakus from Ultimatum to affaire d'Etat!

The 3rd ataluku can be the Full King or Cellulaire of the group lol