You're looking at the the internal logic from within the story when you should be looking at the meta reason for the stalling. Luffy worrying about killing or hurting Bellamy doesn't make sense at all as Bellamy attempted to hurt Luffy even before he got parasited, and he knew that Law would need his assistance against Doffy. Also when has Luffy worried about his punches killing people? That was for the sake of stalling so Law and Doffy can get their character dynamic established, and to weaken Luffy.
Tashigi wasn't even present for the 1st half of Zoro vs Monet. Zoro was simply stalling with Monet, and in doing so he put his crew in serious risk, and Robin had to save Nami and Chopper. Does that sound like Zoro doing a good job protecting his nakama? No. It doesn't.
Against Kamazou, he was literally goofing around with him and Gyukimaru until he got stabbed, then finished the job soon after with a named attack ala Chapter 1110, and if you forgotten, he only fell because he had a poisoned stomach, hence the growl, not Kamazou's attack in and of itself. This was also so Zoro and Hiyori can have their dynamics established after the fight.
Zoro could of finished Pica off way sooner if he simply used one of his faster techniques, yet he didn't opt to use any techniques until Pica became a threat to everyone else on Dressrosa, and only then did he start using his named attacks. This stalling was so that Zoro can be busy, and can't aid Luffy and Law in their battle with Doffy. Same reason why the Birdcage exists.
You keep saying that Cracker and Lucci are the same, yet the context within the fight are so vastly different that they are far from comparable. Unlike Zoro in his Lucci fight, Luffy from the start needed G4, him best form at the time, and used named techniques in it, and still needed heavy carrying from Nami, and PIS from Cracker to get an illegitimate W.
Meanwhile Zoro hasn't used a single named attack, and although he did show Overflowing ACoA in his fight, it's pretty obvious that it was not needed as shown in Chapter 1110. You can't claim that Zoro and Lucci used any named attacks before the current chapter as there is no proof of such. Furthermore as I have showcased in the Zoro vs Monet fight, Zoro has the tendency to stall so shamelessly that his fight can spill over to his nakama and put them in serious danger. So just because Zoro says he serious about defeating his opponents and protecting his friends, that doesn't always come to fruition in terms of action. Regardless, stalling Lucci was in a weird way effective in protecting his crewmates from Lucci's wrath.
But really the meta reason for the stalling was so that the Bonney and Kuma could get their backstories told, Luffy can give Bonney hope in the Sun God once again, and so that Vegapunk can die. If Zoro was present, there be enough powerful bodies on the allies' side to make Vegapunk's death avoidable.