I'd chalk up Tony doing more in the fights to 2 things: 1) more experience with the tech than Rhodey 2) it's HIS movie.
As for soliloquy, there is a comment made by Raimi on the fact that Spider-Man doesn't quip a lot during the fight with Doc Ock due to the impracticality of it during a fight. When they stop to catch their breath, sure. During the actual fighting, no.