then my choice would just be [vote/don't vote], and the web site would handle the percentage choices invisibly

Ah, now I understand your intentions :-)
The frontend should suggest to the user which value they should vote with.
This would go in the direction of making it easy for the user and one click would be enough for the "Like".
In principle, I'm always in favour of automation, but I'm rather "old-fashioned" in this respect. Of course you can give the user the choice of switching on and off, but I personally wouldn't want to switch it on.
However, it would be interesting if the suggestion appeared in the vote bar, but I could still change it.

If I think about it briefly, I come up with the following aspects when determining the vote value (in order):

1. information content, entertainment value,
2. do I know the author? Has he already made an appearance?
3. how much effort could the author have put into the post/comment?
4. post or comment,
5. how often have I voted for the author in the last few days?

And: Exceptions prove the rule. :-))