This is a good question…..
Lightning question: not your keys not your coins, so you shouldn’t store too much in a lightning wallet. If lightning takes off you might have to top up your lightning wallet daily from a Bitcoin wallet. Aren’t those transactions on chain? What happens if 1 billion people want to top up their lightning wallet daily? Bitcoin only supports about 200k tx/day.
Lightning taking off or becoming commonplace doesn't mean that you'll need to top off your lightning wallet more frequently unless you're otherwise having cashflow (satflow) issues. Do you top off your checking account from your savings account on a daily basis?
Since usually only the highest fee-paying transactions get confirmed, topping off daily would incur a lot more fees. Instead, I'd propose making a single on-chain transaction to open multiple lightning channels or just significantly increase my lightning balance.
