Yeah, the main problem with getting people late is that it means you'll miss out on some events.
For example, you get some very funny text if you decide to bring Legion to Tali's trial... but there's no way to do this if you're trying to do a 'save everybody even the Cerberus Crew' run.
I picked up everybody and did EVERY sidequest before I went to the IFF in my first game... I had no idea I was getting Legion there. So I got Legion, did his loyalty quest and beat the game... and I didn't really get any of the 'wow, he's cool!' vibe from him until my second playthrough where I did things differently in order to get more face time with him.
For example, you get some very funny text if you decide to bring Legion to Tali's trial... but there's no way to do this if you're trying to do a 'save everybody even the Cerberus Crew' run.
I picked up everybody and did EVERY sidequest before I went to the IFF in my first game... I had no idea I was getting Legion there. So I got Legion, did his loyalty quest and beat the game... and I didn't really get any of the 'wow, he's cool!' vibe from him until my second playthrough where I did things differently in order to get more face time with him.