Or, one can play a longer term game as I do and give up larger curation rewards by:
Curating everything you vote on and not autovoting.
Still vote on a post that is hours old and pretty much has most all the votes it is going to receive (like this one), because you support the author/message.
By doing this, you strengthen those you naturally interact with (not only the author, but those who came before you voting) and chances are good that sometimes those same people will be interested in your posts and their accounts being stronger as time progresses will allow for them to vote better on you.
And, sometimes one shouldn't think it is about the rewards maybe? There are a few I have kind of adopted who I am convinced will never reach minnow status, yet I like what they post. They enrich my world by posting what they post, and that is more valuable than the fact they will probably always be a dust vote. Who knows, maybe in a couple years I can single handedly make them minnows, lol.
It's an honorable approach to take, but you make a good point regarding that late vote appearing - it is certainly more noticeable than the raft that appear during the first 15 minutes, and could certainly work in your favour, along with a comment showing why the vote arrived. e.g. interest in the topic.
A Red Fish shared, is a Minnow in double time. See if you can get them noticed by c-squared or ocd, or curie :)