Be careful with base shapers--I have hear horror stories of the hard edges putting strain on the corners over time and causing damage, even poking through the canvas/leather.
I used to use base shapers until I read that, and I switched to Samorga organizers. I don't need the organization aspect, but I'm really happy with them. They're so lightweight and do a good job keeping things from escaping into corners--I don't feel like I have anything "extra" in my bag.
I also think it makes a difference visually to add structure to the side of the bag rather than just the base.