Solutions:

• Light-weight fake tree (no toxins or fall dangers)

• No lights (no strangulation or electrocution)

• Large, shatter-proof ornaments attached via string (no sharp hooks or sharp broken ornaments)

They also sell fake "pop-up" trees that are physically impossible for a cat to climb because they have no branches. You should have seen the look of disappointment on our cat when we set ours up.