Technical solution is to create a sort of 2 upvotes buttons. (It's a bit violent and not-refined but...good news, it kind of already exists !!).

• The post upvote button votes with maximun power (based in your current %age)
• The newsfeed one will yield less steem power when upvoting. Let's say half.

The devs already implemented a solution for whales to upvote with limited power, it should be technically feasible to adapt this feature. ( @piedpiper 's latest post talks about this vote slider)