Of the currently active kamis, I would list Kumar, Purna and Ram Kumar as my favorites. However,
all HI kamis do great work.
Kumar ranks with the "old masters" in quality, and he does a wide variety of models.
Purna is a perfectionist. His knives are always perfectly balanced, feel lighter in the hand than their scale weight, and have superb fit and finish.
Ram Kumar is newer to HI, but his work is excellent and he is very creative with new and modified designs.
As for favorite blade, that would be difficult. Earlier this year I acquired a strange blade made by Rajkumar kami, who is no longer with HI. I'm not sure when it was made, but my notes say March of 2011. It's called the "Shiva Knife." From Yangdu's description:
Our new Kami Rajkumar, Prince, has created a beautiful knife for you based on a legendary knife used during the ancient times of the 2nd Buddha Guru Rimpoche. As the legend has it, this beautiful knife was used by the gods for fighting evil spirits.
I find it hard to imagine the degree of skill that it took to forge this complex blade: