I carry 6 rackets, a pair of shoes, 2 bird canisters and assorted accessories (grips, strings, first aid)
Please inform your racket bag code. Judging by the condition you are facing right now, i made an assumption that your bag is a SP Code, or maybe an EX code although it is less likely.
For better built Yonex bag, you could buy a JP code which is much more sturdy and solid , especially when comparing it with a SP bag.
EX Code has slightly better built than their SP fellows, just that little. If you want better, JP bag is the answer, if you want to stick with Yonex Bag of course. If you want to play around, i would suggest Tennis bag such as Head, Wilson, Babolat, from my observation, Tennis bag is quite solid and well built. Furthermore, you could also have a look at Kason 2012 Olympic Edition badminton bag, it is really solid & Lining bag which is endorsed by China players at 2012 London OG too.