I would try a sample of Coloplast - the opaque, not the translucent. The opaque has a Velcro you can tuck at the bottom or just under the observation flap.
Trying to decide if I should request a smaller bag on my next order, currently using Maxi, might try Midi (not Mini). In the morning, I'd probably have to empty frequently, but I have almost no output from noon until the next morning.
I'm petite; I wear girls' 14-16 pants!