I see a lot of people argue that Starfleet is "too militarized," most recently in regards to the STID trailer where someone is given a full military funeral. Indeed, when Yar died in TNG, she didn't get anything that resembled a 21-gun salute.
When you look at the installments that Roddenberry had the most creative control over, Starfleet's militarization is less apparent. In The Cage, they don't even appear to use a full naval ranking system, and the only commissioned officer rank we hear is "Lieutenant." And indeed, their rank insignias seem to indicate there are only two officer ranks.
Then, in TOS, it gets expanded to a full, Royal Navy-descended rank system. But it still rides the line between military force or not. The uniforms from TOS don't look all that military.
Same with TMP. It's clear that, between the uniforms, the protocols, and the rank procedure, the chain of command is not rigid. Decker gets a "temporary demotion" so he can serve as XO, which I don't believe is a practice that most militaries partake in.
But then TWoK happened and Starfleet became a fully-fledged space Navy. The uniforms are much more elaborate and are much more formal. They use naval policies and procedures, like the Boatswain's call. TUC takes it even further in that direction, to the point where a Starfleet Admiral asks if the end of the Klingon Cold War means "mothballing Starfleet."
But in TNG, it goes the opposite direction. Picard is opposed to war games because he does not believe that Starfleet is a military organization. (And odd stance for Picard to take, given that he fought in the Cardassian Wars.) But they are clearly the military arm of the Federation, it's not like the Federation is sitting on some other, more militarized organization. And then by DS9, it's come back around again: not only is the Federation a military, they are involved in a World War II-esque total war.
I would argue that Starfleet has just the right amount of militarization. A lot of people point at their rigid chain of command and conclude that they must be a space Navy, but I think that Starfleet gets a lot of utility out of their rank system even when it doesn't pertain to combat. It's good to know who's in charge, whether you're holding a phaser or a tricorder. And as the only obvious military arm of the Federation, it makes sense that human military traditions would live through Starfleet, such as the 21-gun salute and the Boatswain's call.