I recall there was a discussion much earlier in the thread about how Samus is supposed to be 6'3" yet she seemed shorter than the Space Marines. Well, having beaten the game and viewed all the cutscenes I recall the scenes where Samus is standing next to Madeline Bergman/Melissa and Samus just towers over her. Granted, Samus is in her armor during those cutscenes and that may add some inches to her height, but still her stated height of 6'3" seems reasonable.
However, standing next to Anthony and the other Marines Samus doesn't seem so tall at all, but I guess you could just explain that by the Space Marine being super tall as opposed to Samus not being tall. If Samus is 6'3" then they might be 6'6" or even taller than that, especially so if some sort of bio-engineering on them was involved. The Space Marines might be the NBA of the future.
And later on when she runs into Adam before he goes on his suicide mission there is a cutscene with Samus in only her Zero Suit talking with him for the final time, and she didn't seem very short in comparison to him then. So I don't know what the deal was earlier in the game... and also in the scenes which show very young teeny bopper Samus she is very short. Maybe something happened to her when she got the Chozo suit that also made her height grow as well? Because I don't think an adult grows that much higher after their teenage years, but I'm no expert.
Anyway, it just seems like whoever was involved with making the cutscenes didn't do a very good job of keeping the characters' heights consistent. In some scenes Samus seems like she might be 6'3" like in her bio, but in others she might seem like only 5'3" or something. Its weird...
ETA: But now that I think about it, it might have been done intentionally for artistic purposes. You know how she starts out young and immature but she grows and matures throughout the story? Well, maybe she was made intentionally short to emphasize her childishness in the beginning, but by the end she is more mature and her character's height has grown to match her maturity. Or something like that... I dunno, I'm kinda just running my mouth at this point.