My favorite thing to carve is always something that I have not created before or carve it in a way or position that is challenging.
I am always willing to give input and advice on a customers creation, but I usually mention that they are the one who is going to see this carving daily and if it is in a prominent place it will represent them,.....so they should order something they want to see and enjoy.
It is common and usually expected for a chainsaw carving to get cracks in it over time. When we carve and seal a piece of wood and then it is brought inside at your home, it dries out considerably. Because of the nature of a log, where the outer rings and the interior dry at different rates, cracks occur. Many times they add to the character of the piece, but they can be fixed if needed. When a carving is outdoor, there are many elements that effect it. The constant warming up and cooling down.... rain.... humidity changes all make small cracks occur.
Chainsaw carving is becoming more popular in the last 10 years. I always tell people who are interested in trying it that they should try carving with chisels or a dremel first to understand the process of efficiently taking material away. I carved with chisels for 10 years before every owning a chainsaw, so the saw was just a bigger tool. I have talked to many beginners who got frustrated with the dust,exhaust, danger, and weight of the tool while trying to learn.