In any case - your points against redistricting are good. But even a "temporary" solution might have centuries of value, so I don't think it's entirely unreasonable to make a pragmatic push for limited redistricting, specifically only splitting large states - fusing states is much harder (because which laws apply?), and given population growth, it's pretty reasonable to have more states. Judging by the size of the house - which is probably too small, not too large - the senate has a lot of room to grow. We could certainly afford splitting all of the large states without causing huge issues - if people actually want that.
But a more long term solution without redistricting is to give up on the notion that states are equal. Just give more senators to larger states, and fewer to small states, and the current system mostly works; certainly better than now, and without the need for as radical an imposition as state-level redistricting.