I need a vest

I am usually walking around with my big LowePro backpack containing all (or most) of my gear. Its a fantastic backpack and really comfortable, but switching lenses is a pain if I have to take it off and put it back on all the time.

I also have a slingshot bag that makes this slightly more bearable, but this one is far less comfortable and cannot hold as many items.

I have thought about getting some kind of vest, where I can put on my most often used gear (1-2 lenses, filters, cleaning equipment) and keep all the rest in the backpack. It appears most systems are quite modular, but there are so many options I just don't know where to get started, and I don't want to miss a good option. I have absolutely zero experience with these things - can anyone make recommendations?