I thought of answering your quiz;)

Here it goes:

I should complain publicly and demand an explanation from those responsible for the downvotes immediately on my own blog.

Often only works if you tag the names you got the downvotes from and where that leads, we know. Gets a no. Unless ... you're setting it up for all the called to come and spank you. Could be interesting, though (for all others who read and comment).

I should complain publicly and demand an explanation from those responsible for the downvotes immediately on their own blog.

One will not like the answers. So pointless. It would be like if someone is mean to me and I ask them "Why are you being mean to me?", I give them an opportunity to tell me how stupid, brash, lazy or otherwise uncreative I am (unless I want to learn to grow from the insults as a training ground, in which case that's a super thing to do). Get's a yes in case I am in the mood to sacrifice the account I used for this (If I have only one account, I wouldn't do it. Which is the case with me).

i should keep quiet and seek support from influential users who oppose the downvotes and could help me stop them.

This is worth considering but not acting out necessarily, because at that moment you have to ask yourself if the cause is important enough. Already the pain is put into perspective, isn't it? So, a good way to check if the drama is real or just imagined.

I should keep quiet and find a way to get back at them by repaying the favour in some painful way within my means.

Not worth it because it's not fun unless you have a bunch of connections and money, but then you wouldn't have gotten into the situation you want out of in the first place. LOL

I should write and publish a series of informative posts for the entire ecosystem publicly denouncing the abuse and arbitrariness of these recidivists.

Only succeeds if you are an excellent stoic and possess a calm and ignorant attitude to any backlash and downvote that accompanies you. It takes a lot of ass in the pants. If you don't have that, better not.

i should just keep creating and posting my content, as always, with the same frequency, and commenting and interacting all over the place as if nothing happened or is happening.

That gets a "yes".

Thanks. That was fun :)