Unfortunately, removing the metal frame that holds the current Tumi monogram patch, will leave a hole where the metal frame is affixed to each Tumi bag.
Tumi shifted design from directly stitching Tumi leather monogram patches onto its products, to affixing the metal frame that holds the 3M adhesive leather monogram patch in the late 90s/early 00s.
I would not recommend removing the metal monogram frame from modern Tumi luggage products.
Best option is just to leave the leather patch nude and not monogrammed.