I don't think PS weapon swap times were too slow. Have you ever tried to swap RL weapons? (not to mention the huge size and weight of weapons like MCG+Striker, or the JH+deci)
If you want to do it fast (to switch to sidearm or knife), you would have to drop your main weapon. That way you spare most of the movement needed to swap your weapons and you can do it really fast. If you want to keep your main weapon, it must take time till you holster it and pull the new one.
Hunting realism in a sci-fi shooter game may sound odd I know. I don't say that it should take 10 mins to have your rexo properly fitted on you...
But these weapon-related issues should be kept closer to realism. IMHO.