Having watched the original series and Endless Odyssey, I wasn't sure how much I would like this movie. I still looked forward to it and finally sat down and watched it. First the art and animation. Obviously it is a beautiful film and the action scenes are top notch. The Arcadia does it's classic ramming technique a few times which is sure to please long-time fans. The designs for the characters and settings were also amazing, so if you don't like anything else about the film you'll at least enjoy looking at it! I will say, though it's not much of a gripe, I did thinkit was a bit odd that the characters all looked like regular people instead of the usual Matsumoto style. I can understand why they made this choice, however they included Harlock's bird which took on the same stylistic appearance as the original series while everyone else did not.
The voice acting, I watched the dub and read the subtitles. I noticed in the subs the names of the characters are different which can be distracting. Overall the voice acting was good, Harlock was spot on.
As for the characters and plot, this is where the film starts to fall apart. Speaking as a fan of the series, I couldn't help but be disappointed by the lack of vital characters. There was no Daiba or his father, only a replacement for him named Yama. A few other crew members that appear in the other series were also missing but that isn't a big deal. Kei was a bit more sassy than she usually is and Harlock also ended up being more selfish with his goals which I consider uncharacteristic. Miime also did not play her harp for some reason. However, Harlock, Yattaran and Kei were good on screen and had more investment with the audience than Yama or Ezra. Even with Ezra's redemption I still did not like him as a character. I'm probably just biased because of Daiba not being in it but I also did not care much for Yama.
The plot was interesting, some parts were a bit boring but I think that's mostly on me. There was one thing that I didn't like about the plot and that was it's redundancy. I noticed similarities in the story to other movies especially a few that came to mind immediately while watching. I did enjoy the ending and look forward to possibly another installment.

I'm probably being a bit too harsh here but those are my thoughts. The movie did keep me entertained throughout, I enjoyed seeing my favorite characters again and I'm sure others will enjoy it, especially on the big screen!