I can understand your concern.
But,i would point out to Skyrim, Morrowind, Oblivion. Freak, any game from Bethesda Dev Studio (notPublisher, the Devs)
Their games, are basically timeless, because of mod support.
Today, i can download my morrowind and with a couple of hours of looking through nexus, i can have a way better experience than i had in the past.
Same with Skyrim.
And those games had the same problem of lots of "mods", or "Tweaks" during the first few months of the game out.
But, at the long term, what keept the games alive for years were mods.
I didn't play Warband,but for what i've seen around the community, the same can be said for that game, the lifespam of a game from 2010, even with expansions,been actively played at 2020 is amazing. And it's not only thanks to a good game, but thanks to modding.
Give time, wait for the modding tools to come out, and specially for the devs to finish cleaning the base game and putting all the features in.
Until then, the early, more crude mods are here to be an helping hand.
About people complaning about broken saves on EA game and specially modded game.
It's innocence. At least i would point out that those people, are probably people that have never meddled with early level stage modding. Specially on a EA game.
Freak,i lost count of Colonies i've bricked on Rimworld while it was still on Alfa, no mods. Just because a patch broke the previous colonies.
That's part of the dangers of buying a EA game, specially a complex game like RW and Bannerlord are.
But look at RW now. Out of EA, first Expansion on, and the modding community even helped the devs into adding features, that the community at large wanted and the devs haven't thought of yet (I'm looking at you bridges...)
And of course, the modding community of RW now is so freaking big, that there are mods that could be seen as real expansions, like Rimworld of Magic, Rim of Madness, Save our Ship that freaking added SPACE BATTLES on what was originally a simple colony simulator inspired by dwarven fortress but with guns.
So again, have patience, if you don't, go back into Warband and wait for Bannerlord to get into a stable, out of EA state, if you don't want to deal with bricked saves.
Sorry for long text, but god dammit, modding is a passion of mine. I really should learn how to code...