I have seen Camellia's in their natural form and others pruned to tight balls. I prefer them natural but wondered if pruning was better for them.
I too prefer to let them develop their natural look and prune only to remove dead wood. Controlling plant size is not an issue as min shrubs grow slowly enough where that is not a problem. Doing espalier arrangements sounds interesting but I can never find the time so I am passing on that for now.
Here is a link that might be useful: Article on pruning by the American Camellia Society
Pruning of camellias is rarely 'better' for them. They should be planted in a location that accommodates their adult size, if possible. If you see any rubbing branches, remove one; any broken or damaged branches can be pruned; conservative shaping is fine....but should be done to open up the plant, rather than shape it like a ball or cube.
That always looks so silly, don't you think?