Five Compliments not to Give a Type 4:
1. "You deserve to have 'x'."
Especially when the type 4 is coveting something that they don't have, and likely won't have. Saying that they deserve it will make them yearn even harder to achieve/obtain 'x'. Best to say that you understand how they feel about 'x' and show you sympathize with them, but don't kill or fuel their dreams. Better to suggest a creative outlet for them to achieve something that is related to 'x' and will be rewarding in the end.
2. "You may be emotional, but I admire your passion."
Don't ever tell a 4 that they are too emotional. It makes them feel that their emotionality is a defect, and they will get depressed afterwards.
3. "You look just like <insert celebrity name here>."
If it's a celebrity that they admire, then they will like it initially, but ultimately, it will end up becoming a compare-contrast moment between traits that the celebrity has that the type 4 has, and the traits the celebrity has, that the type 4 doesn't have... and they will end up focusing more on the traits they don't have. Just tell the type 4 they look handsome or beautiful.
4. "This piece of artwork is very good." or "This piece of artwork is not too bad."
The word "good", or "not too bad", denotes higher than mediocrity, B work, and type 4s will think that B work is commonplace.
5. "You're pleasantly unusual."
Type 4's don't need to be told they are unusual, they already feel that way. It's like casting them into the Island of Misfit Toys. Just say that you love how unique they are.