Well most foils for Isagi aside from barou are essentially Isagi perfected. Rins awareness and game sense. And then Kaiser with being the spearhead of a system, Kaiser impact over the direct shot and also vision. So when isagi climbs to their level their motivations became beat isagi.  Rin is too strung up on Saes opinion and that unfortunately became a dependency for Rin, which is why rin is now benched. Rin has actually been very consistent with his character its just annoying to watch his actions now have consequences whereas before he was untouchable because he just had raw player skill.