The Montreal Convention limits the carrier's liability to approx. $1,600 per passenger. And that is fair market value, not replacement cost. In other words, a $200 shirt worn 5 times isn't worth anywhere near $200 now.

Short answer is that if you want more coverage, you can either purchase excess bag coverage at check-in or carry insurance through your CC or other policies.

Check the policy limits and whether it provides FMV or replacement cost for your lost luggage insurance. Also, check the exclusions for the policy.