The Tektro RRL brake levers are arguably the best drop bar brake levers I've ever seen. The Tektro RL-340s & similar models (short pull version) are decent, but could be made more comfortable (in my opinion) if they had a smooth transition between the hood & the tops, in a modern style (see any current Shimano, SRAM, or Campagnolo brifter-to-handlebar transition).
Flat transition: https://coresites-cdn.factorymedia.com/rcuk/wp-content/uploads/2015/06/Specialized-Venge-ViAS-Tinkoff-Saxo-Peter-Sagan-04.jpg
TRP packages an extra shim with their RRL levers to achieve this effect: http://trpbrakes.com/pubs/RRL%20Brake%20Lever%20(B5).pdf (instructions).
Purely by guess, I think the shim may also work or be easily adapted to other Tektro models, & maybe beyond those too; I'm assuming the plastic body is roughly the same where it contacts the handlebar, so filing could bring it into a good shape.
Here is a picture of the shim: http://biketouringnews.com/wp-content/uploads/2012/03/IMG_2999.jpg
Perhaps using 3D scanning, the shim can be modeled for ease of 3D printing.
Without the shim, users are forced to choose a very "classic" hood-to-handlebar position (https://farm8.staticflickr.com/7063/6936342796_7a6741ee54_z.jpg) which hurts my & probably other people's wrists.
You can either do #1 (above) or #2 position them so the hood is flat, but that forces the whole body to move down past the tops: http://cdn.velonews.com/wp-content/uploads/2015/05/26.jpg
I've been getting by using old/broken Shimano brifters as brake levers, but this can be an expensive/hard-to-get alternative for other people.
I don't have one of these lovely brake levers though, & guessing the (intricate) geometry behind them is out of the question. Does anyone have one?