When new players ask me what type of cue they should buy I always try and steer them towards a carbon fiber shaft. Not because it will make them a better player, but for things like ease of maintenance, no warping, easy to clean, doesn't dent. I also don't see the point of learning how to shoot with a wood shaft then re learning again if you want to switch to carbon in the future. Yes there is a learning curve when switching from wood to carbon.
As for myself, the carbon shaft made me a better player after I switched. Because of the energy transfer with carbon I am able to shoot softer and still move the cueball around which ends up with me pocketing more balls than if I hit it harder with a wooden shaft. For most people who are not pro players and can put in hours of practice time a week, shooting softer will help you pocket more balls.
Cost was really the only thing that newer players would stuggle with, but with the Jflowers, Konallen cues that really became less of an issue. They might not be the greatest cues in the world, but for a beginner they are perfect. If the beginner doesn't stick with it, a carbon cue almost always has a higher resale value if they want to get rid of it or trade up to a nicer cue.
