Hey, it's your opinion. There's no reason why a sling will look 'cooler' than a bag to everyone.
The thing about bags is not to store as much as you can, but have the bag be able to bring just what you have or want to bring out. I seldom use my primus AW unless I'm going to school or church because the top compartment will only be filled with books or jackets. Only when I get my 70-200 will I use it a lot more, especially since I have a tripod that can be mounted to the back.
I would say, for your kit, flipside 200, or slingshot100 is more than enough.
Cheers,
Zexun
Will consider your suggestion. Thanks!