The Protoporos arc has been a little bit different to be fair. A lot of the gambles we've seen thus far have mindgames and stories being told that occasionally get put to the side to show big fight scenes (like Hangman, the Tower arc). Protoporos is a lot of smaller, shorter gambles that have tended to be straightforward (like Kaji vs Floyd Lee), and a great deal of fighting culminating in the current Protoporos Nightmare. I can see where it might be tough for someone who may have read a lot of earlier gambles while they were already scanlated (so they can blast through the fight scenes) to come up to our current point and wait for the batches to see theyre mostly fighting, and the story is framed in a bunch of flashbacks/flash forwards. The Tower arc was a bit similar, you had long portions of the story tied up in the Ranko party and police vs Kakerou / car fight. I agree with Lithe that I think the Ban format has a lot to do with it; its supposed to be a bunch of smaller gambles under the umbrella of the large gamble to become the Kaiser, so its different. I think it's just supposed to be like this, with a bunch of blank spots for now that will be revealed in time.
Hal told Nobuko to lose so he could place her under Kakerou's protection, it wasn't shown because it wasn't important. It was just important to know that 1. Hal promised to protect Nobuko and is prioritizing that, and 2. Hal was on Usogui's side the entire time, and they were able to communicate that to each other without stating it directly and tipping off Lalo to the plan. They've explained why Usogui's plan was airtight and clever, he and Hal made Lalo think Shoudo was still standing by posing as Nobuko and trapped him in an unwinnable situation, they just did not anticipate Lalo's ability to counterattack so swiftly and strong.
However this arc is pretty important to the overall theming of the manga, which is that to truly win your gamble you need a way to enforce that win, otherwise the side with power could just not pay or kill you outright. For the most part Kakerou has been that kind of force and is unassailable, but we've seen the author play around with this theme, like Oofuna losing the gamble but being able to incapacitate Lacy and survive. But now Kakerou has to deal with the full might of Ideal and Lalo basically "flipping the table" and trying to overrule the gamble with pure force. It's probably a bridge Usogui had to cross at some point, with how much they built Ideal up and how much Kakerou has been an indomitable wall up to this point. Kakerou is supposed to neutrally enforce all gambles, but they cannot do so if they are not the strongest force. Lalo is banking on turning Kakerou's rules for the Ban against themselves and making it so he will win the gamble on pure force, which Kakerou by the letter of the law will have to accept because the only rule is the Kaiser on the 31st is the winner.
It's a subject some gambling manga have tried to breach before (Kaiji is currently going through an arc where Kaiji legitimately wins billions of yen but has to go into hiding because Teiai would just take the money back) but usually they gloss over it and the hero is allowed to walk out with massive amounts of money no problem. It gives this series a unique charm that I appreciate. I too was not really a fan of the huge amount of time devoted to the ridiculous battles when I first picked this up, but I've come around to it.
Another theme the manga runs with is that there is no invincible gambler that keeps winning; Baku's original run to Surpassing the Leader was as a straightforward Kakerou member. He realized that his allies at the time were allies of convenience or were only allied with him because he kept winning. When he lost and Kyara left Kakerou, he was able to change his approach. Baku was able to amass a group of genuine allies this time and has been able to overcome situations where he was outmatched or it was a 50/50 gamble because of those allies. We saw this most dramatically with Kaji's gambles, where he was able to beat Ikuto thanks to Karl's help, and his last gamble with Floyd where he was able to move his heart and make him give up. These things are just as important to the overall story as Baku steamrolling people with his clever plans and mindgames (like what he did to Suteguma, he completely outplayed them but also was able to sway Ranko's party to give him more of an edge).
Judging from the covers it looks like Lalo and Baku eventually have a 1v1 gamble to decide the entire game if that's what you're waiting/hoping for.
As far as this arc in particular goes, everything was at the least hinted at as a possibility. The only thing that didn't feel as directly hinted at was Lalo's actual plot for becoming the Kaiser with the armor, and that can be chalked up to the author not wanting to directly spell it out in Ch. 341 about what the armor of indominability does, because that would make Lalo's plan dead obvious.
That aside though, @Nehona what scenes were not shown, and what opponents got off-screened?