After thinking about
Should the weight of downvotes be increased?
which I declined for the reasons specified in my answer, and
Please charge rep for questions after threshold
I have a proposal.
How about if question upvotes were only worth +5 rep instead of +10? And this was applied retroactively? (answer upvotes would be unchanged from the current behavior, so this would be question specific.)
This seems to be a better solution to the particular "shore, there is always gold" problem without all the rather serious negative repercussions of increasing the punitive value and/or cost of downvotes across the board.