First, congrats on the alpha version of democracy 4, it is really fun to play!
My thoughts on voting balance:
I ran through a game as a liberal socialist (randomized start), and the voting results (maybe 3 election cycles in) are heavily skewed in my favor. For instance, I received over 97% of the votes in the last election (I have over 99% voting intention). I suggest giving parties more voter loyalty and/or allowing the other two AI parties to adapt their views to get more voters. Furthermore, the membership for my party is over 60 million, the next party has about 100,000 and the last party has 0.
Another thing I ran into is that some voters just give me their votes. For instance, I have 0 happiness with capitalists, yet I still get all capitalists above the 50% line (in happiness distribution). In that same distribution, I would guess that their happiness is about 80% (most are very close or on the fanatically supportive side), yet their current opinion of government is fanatically opposed.
Lastly, I am so happy that you made this game!