Just hosted channels all the way down.
I wouldn't build a new LN, though, since this one already has too much network effect, and network effect is everything. That is the lesson shitcoiners have never learned.
OK, I think we can do something that isn't just hosted channels. It would be like
  1. Channels only keep track of balances, not of HTLCs, this simplifies everything
  2. HTLCs are trusted, balances are not
  3. Channel balances are public so routing is much better
But depending on the issues you're seeing lately this may not be enough. It would still be shitty. I think hosted channels is probably the best solution.