You're viewing it from a PoV of a player who already completed the game. I'm talking about my first playthrough.
The Alliance actually does something. They send investigators to Freedom's Progress (that's why you head there ASAP, to get there before the Alliance), the reinforce Horizon and sent Ash there (yes, she was saved in my first playthrough
). Anderson doesn't trust me though and I can't get back to Alliance, thus I'm forced to work with Cerberus.
There is no indication of the scale of Collector forces. They kidnap entire colonies, there is no telling how many of them are there until you get to their base.
The way the story unfolds provides a certain tension and desire to end the Collector threat. I can't say the same about ME1. Stopping Saren was never something I felt I should do sooner rather than later. I just rolled around galaxy in the Mako 
The game was engaging due to its storyline when I played it first. I didn't really notice the importance of the squadmate missions in the game. Only after finishing it and looking back I understand that the driving force behind the game are the characters and not the story.
Nope, that was my POV since the first playthrough. After the first 15 minutes, I realized the storyline went to hell. I wasn't pessimistic though, but throughout I was like, what the hell, why are we after the collectots? Why am I working for cerberus? I need to take down the reapers! WTF game etc...
The alliance does nothing, if they did, the colonies wouldn't get abducted. And even if they were, and they didn't, WHY DIDN'T THEY DO MORE?
No scale of the forces of the collectors, no telling how many they are. Back then we only knew it was once ship. One ship, vs the galactic organic force. All the more reason to realize, how stupid the suicide mission was, and that the only reason it worked was... plot.
The collectors will attack earth, garrus says, as we walk through the most obvious trap ever on the collector ship. After that we destroy the collector ship in 2 shots. At the climax of the game. GG.
Its this lack of common sense that is driving me crazy sometimes, I'm stuck wondering, WHY doesn't anyone consider those simple things? And how do some of these people blame ME3 for not handling story so well, when ME2 failed as a sequel?
As for ME1, it was different, no time constraints for sure, but so is ME2, right before the collector abduction. I agree ME2 did better with time mechanics, but it falls apart when its nonesense leading you there, and nonesense that makes everything work out for you.