Factions/Lore and Champion Place and More...
OK, so we pretty much have champions aligned to a certain faction or at least related to, and have a role/contribution to it; but we also have a pool of champions listed as "Independent" because/which means there is no place for them in this "Fiction Universe" and I can see the reason of why the Lore changes had to happen. To make a more clarified vision of this topic:
Ionia
Ahri (related)
Akali (Kinkou Order)
Irelia
Karma
Lee Sin
Master Yi
Shen (Kinkou Order)
Varus
Wukong (related)
Yasuo (related)
Zed (The Order of Shadows)
Shurima
Amumu (related)
Nasus
Rammus (related)
Renekton (related)
Sivir
Xerath (related)
Skarner (related, Brackern race)- Azir
Freljord
Anivia (Avarosan)
Ashe (Avarosan)
Braum (Avarosan)
Gragas (related)
Lissandra (Frostguard)
Nunu (Avarosan)
Olaf (related)
Sejuani (Winter's Claw)
Trundle (Frostguard)
Tryndamere
Udyr (related, Winter's Claw)
Volibear (related, Winter's Claw)
Zaun
Blitzcrank (related)
Dr. Mundo (ralated with Noxus)
Singed
Twitch
Viktor
Warwick
Zac (related)
Piltover
Caitlyn
Ezreal (related with Shurima)
Jayce
Jinx
Orianna
Vi
Zilean
Noxus
Cassiopeia (related with Shurima)
Darius
Draven
Katarina
LeBlanc
Morgana (related)
Riven (related)
Sion
Swain
Talon
Urgot
Vladimir
The Void
Cho'Gath
Kassadin (related)
Kha'Zix
Kog'Maw
Malzahar (related)
Vel'Koz
Bandle City
Corki (related with Piltover)
Gnar (related with yordles)
Heimerdinger (related with Piltover)
Kennen (Kinkou Order)
Lulu
Poppy (related with Demacia)
Rumble
Teemo
Tristana
Veigar
Ziggs (related with Piltover)
Shadow Isles
Elise
Evelynn
Hecarim
Karthus
Lucian (related)
Maokai (related)
Mordekaiser
Thresh
Yorick
Demacia
Fiora
Galio
Garen
Jarvan IV
Lux
Quinn
Shyvana
Sona (related with Ionia)
Vayne (related)
Xin Zhao
Bilgewater
Fizz
Gangplank
Miss Fortune
Mount Targon
Diana
Leona (Solari)
Pantheon
Other
Aatrox (unknown, Darkin race)
Alistar (The Great Barrier)
Annie (Voodoo Lands)
Brand (unknown, cursed soul)
Fiddlesticks (unknown, related with Zaun)
Graves (related with Bilgewater)
Janna (related with Zaun)
Jax (unknown, a mercenary)
Kayle (unknown, another world)
Malphite (unknown, elemental)
Nami (unknown, Guardian's Sea)
Nautilus (unknown, related with Bilgewater)
Nidalee (Kumungu Jungle)
Nocturne (The Twisted Treeline)
Rengar (unknown, The Great Barrier)
Ryze (unknown, a wise being)
Shaco (unknown, a mad killer)
Soraka (unknown, related with Ionia)
Syndra (unknown, related with Ionia)
Taric (unknown, crystal guy from another world)
Twisted Fate (related with Zaun)
Zyra (unknown, Kumungu Jungle)
As you can see, we have a huge pool of champions that don't fit in the other factions or simply don't have a place in the world. Those champ's lore were made just as an introduction of why they are here, some of it doesn't even make any sense, and some just say "Hey, I'm here, ready for action!". You can see why Riot is make the lore changes and re-adjusting some of the current lore to make certain champions fit in the world.
Some lore needs a more in-depth exploring, like Mount Targon and Bilgewater. All those champs in "Other", a huge pool, it's roughly around 20% of the champs in LoL which is in need of a fix and more integration to the lore world itself. There's a lot of potential for a rich lore and more "feeling developing" (let's say like a story or soup opera) that can be brought to light if Riot manage to make the fix, which is what they are trying to explain and do.
For example, look at Kayle's and Morgana's lore, it just don't make sense. The Summoner's summoning beings from different places/worlds to fight, the Institute of War and having random guys just fighting just for it, even though it looks fine on paper, it's just not good as a Lore and it just limit itself from developing a more richer and broader foretelling.