Please add more glass cages, there are only 11, and there are many more that can be added.
Some ideas for them
• Hell Cage (Nether Bricks / Red Clay)
• Frozen Cage (Ice)
• Slime Cage
• Rainbow Cage (Colored Clay)
• Redstone Cage (Redstone blocks / Red Clay)
If those wouldn't fit the 'theme', because all cages so far are only out of stained glass, then I suggest adding 5 more that are missing.
Some ideas for them
• Hell Cage (Nether Bricks / Red Clay)
• Frozen Cage (Ice)
• Slime Cage
• Rainbow Cage (Colored Clay)
• Redstone Cage (Redstone blocks / Red Clay)
If those wouldn't fit the 'theme', because all cages so far are only out of stained glass, then I suggest adding 5 more that are missing.