Tube CAD's SEPP article:
Valve Electronics cathode follower article:
Lots of good reading there about the theory / pros and cons of the design used in the Little Dot. The bottom line is price, the Little Dot amps were designed the way they were because it is the cheapest way to make these amplifiers and get them to consumers.
Do you have a channel imbalance in your MKIV? There is no way to adjust the tube biasing without changing components on the board. If you are going to go through that trouble it would be better to obtain an amplifier where adjustments can be tuned to your liking, Decware or similar amplifiers would provide this option.
Possibly purchasing matched tubes might solve any perceived imbalance issue in the Little Dot, but that is a solution you would have to try by actually testing out a balanced pair of tubes.