Have you ever wondered how Digimon Frontier might have gone if the Spirits of Steel, Wood, and Earth had been bequeathed to Ophanimon, the Spirits of Water and Darkness had been bequeathed to Seraphimon, the Spirits of Flame, Light, Ice, Wind, and Thunder had been bequeathed to Cherubimon, and the protagonists had been Katsuharu, Teppei, Chiaki, Teruo, and Koichi (with Koji joining later)? Mind if I send each episode to your inbox so you can say how you think they'd go in that scenario?
Nah, you don't need to send me each episode, I'm not a professional fanfic writer, so I wouldn't bother with a full re-write.
For your specific questions:
**Ofanimon having Steel/Wood/Earth would mean those would get Transcendent Forms, and by proxy Susanoomon would initially be three-part combination.
***Steel would probably be based off Ein Soph like Timelords in 5D's, Wood would probably based off Chinese Wood Dragons in Chinese alchemy, Earth would probably based off Regigigas's origin Oumitsuni, or Surtr to keep Grottomon's lore European.
****This also would mean Junpei would be the third primary member, so I guess we would be closer to Hunters.
**Seraphimon having Water, and Darkness would imply Izumi would be Tomoki would be Darkness, so we wouldn't be able to do the Leomon reference. Or Koichi would be part of the team, so the conflict would be with Tomoki, which would be very funny, considering Tomoki is a game genius.
**Cherubimon having the spirits of the canon main cast would mean their final forms wouldn't be showcased, except maybe Fire, assuming we give that to the twist antagonist turned protagonist cast member.
***Canonically Spirit Forms don't change except Darkness, so the Forms would be the same, but used for antagonistic purposes. Though I suppose one can be more clever with designs, with Fire being corrupted to look like a Dark Agnimon, similar to Agumon (Black), Chackmon being closer to Hyougamon etc. Frontier era didn't have a lot of Digimon to reference off, so being closer to original era's feeling would be bit difficult.
**For the protagonist cast being switched off with the side team, well, the initial change would be that Koichi's demand to find Koji would be in the immediate conflict with the rest of the cast, and taking Koji back would be more difficult since he has no memories of Koichi. So Koji's arc would have been longer.
***In that same manner, if the canon cast became the stranded kids, Katsuharu, and Teppei trying to convince Tomoki would be more difficult than the other way around, since Tomoki is younger, and wouldn't have been forced to take the initiative. So the two episode arc in the canon would probably a 5 episode mini-arc in the Royal Knights episodes.
***In a similar vein, if Koji became the Evil Warrior of Light, you could take the more Knights Templar route with the Warriors of Evil, with a significant amount of the plot being focused on historical pressures Bestial Digimon went through, and Koji sympathising with them.
****This also would probably mean Warriors of Evil would default to Beast Forms rather than Human Forms.
This isn't exactly an idea that would make Frontier better necessarily (most of Frontier's issues are external to the Series), but a rather slight change like this makes the situation more interesting.
