Bigger blocks do not scale. It's just kicking the can down the road and opening a can of worms.
Offchain transactions do scale on the other hand. You can have as many offchain txs as you desire.
Comments?
And how many offchain transactions will you be making if they're so great? You say "offchain" like it's no big deal, but what you're proposing is a two-tier service. Guaranteed security for anyone on the blockchain, risk for everyone else. Placing trust in a third party to handle transactions for you kind of defeats the purpose of this whole idea, doesn't it?
What's the problem with a
trusted exchange doing an offchain tx to a
trusted payment processor or wallet?
If a service is dishonest it doesn't matter if you deal with it on or offchain.
If a service is honest it also doesn't matter if you deal on or offchain with it.
Point is: it doesn't matter with big (trusted) services if you're dealing on or offchain. Saves you txs fess too.