I'm in favor of a no-party system (for a whole host of reasons that I won't get into). People would run on their merits and their merits alone. Hopefully that's what they do in the Federation. I think it's just as well that Star Trek leaves it vague and doesn't get into it.
I understand why some people (mostly Americans, tbh) say that, but I think that's highly misguided. US politics are already way too much about charisma, "electability" and identity. At the end of the day, what matters isn't who smiles the most or who matches your identity best, politics should about policies.
The focus should be on a manifesto, not a person.
On "electability": that's basically voting for the person you think others will vote for. Aka strategic voting, which isn't a good thing for democracy.
Except it's even worse in the US, because the media tells you who is "electable", so it's voting for the person the media will tell you others will vote for. You end up with 2 corporate candidates (one of them in clown makeup), while the one candidate whose policies would have actually helped the American people is sidelined. Twice.
Anyway, then there's the issue of feasibily: a no-party system seems impossible to achieve. Just like having more than 2 dominant parties in a first past the post system, by the way.
A proportional system has issues (deadlocks being the most salient - and I should know), but at least it allows diversity of ideologies.
Anyway, I just wanted the person I was replying to to know that the US != the world. Roughly 200 other countries not to forget when talking about the world.