I think a 1mb block size is the best we can have now.

Large enough to handle over half a million transactions every day.
Even a million or more with some batching and optimization.

But yet small enough to be able to fully sync the blockchain in 1-3 days.
And fast enough to run over Tor, which might be needed if governments start to crack down on it.

What is a 1000 GigaMeg good for if that means bitcoin will be censored in many places?