In my opinion, there’s nothing wrong with UNI holders being able to get interest on their UNI tokens outside Uniswap.
If the preparation period (voting delay) is introduced, UNI holders will be able to keep their UNI whenever they like. And mobilize them if they wish to vote on an important proposal.
It is by far the easiest and the cheapest solution to the problem.
On a side note, I don’t think there is a big chance of Binance being a threat to Uniswap governance.
There is a decent possibility that Compound will transform Uniswap governance, bringing more power to large UNI holders.
There is a proposal there that will allow for UNI held there to vote.
By the way, currently, Compound offers 5.88% APY on UNI.
More ‘minority’ votes will unwillingly vote the way the ‘majority’ wants with that system.
But it is up to COMP holders to decide that.