I think we would all prefer it if QWERTY wasn't what we grew up with and what we still have to use occasionally, but the fact is that it is, and keyboard layouts should take this into consideration. QWERTY-compatibility comes with a couple of advantages:
The layout becomes easier to learn.
It's easier to switch between QWERTY and the keyboard layout.
Less of the experience you've gained typing QWERTY all those years will be lost.
The last point isn't the same as the first: once you've learned a keyboard layout well enough to say you're comfortable with it, you still aren't as fast with it as you were with QWERTY. You might not make mistakes that often, but it still takes more time for you to process which key to press next.
I feel the importance of QWERTY-compatibility is often overlooked, and while Colemak does a very good job being similar, I decided to look for a way to improve Colemak on this front with as few sacrifices as possible. There's also the ASSET keyboard layout, but it had exceptionally high consecutive finger use (using one finger twice in a row), so it was better to use Colemak as a basis.
So, for people who want Colemak's efficiency on a more QWERTY-like layout, here's the Colemak Lite layout!
Differences (vs. Colemak)
R and S are switched. (honestly, I don't see why Colemak doesn't do this.)
P, G and D are 'cycled' between positions.
EU and IY columns are switched.
L and F are switched.
What it has to offer (vs. Colemak)
Improved QWERTY-compatibility: the S and the G are at the QWERTY positions, and the I (i) is under the same finger (this is more important than you may think).
A more balanced heat map: of course, Colemak has the most common letters on the home keys, but the next three most common characters (HLD) are all under the index fingers. Colemak Lite places one of them, namely the L, under the left middle finger. I personally find this a lot more comfortable.
More hand alternation: by switching the L and F between hands, the left hand is used slightly more, but still less than the right hand.
On-par consecutive finger use and finger travel. It depends on the text you test it with, but I actually had a lower CFU with some books. The difference in finger travel is insignificant.
Difficulties
If you look closely, you'll see that the EU and IY columns on the right side are switched. Again, this is for QWERTY-compatibility regarding the I (i). It does mean you're relearning 4 characters for an advantage regarding only 1 character, which will be pesky at the beginning, but when you consider the years you've typed the I (i) with the middle finger, I feel it pays off. I've used Colemak a couple of months and relearned those two rows in a week.
Next to that, the placement of D on the top row and the shifted P might feel awkward. This was done in the favour of keeping the G in place, regardless of the fact it isn't used too often. To me, moving the index finger upwards isn't really less comfortable than moving it sideways, the only problem was getting used to it, which I did quickly.
Get Lite
For Windows (PKL package)
For GNU/Linux
For GNU/Linux (for use in ttys, when you don't use X)
Instructions for GNU/Linux
cd to the directory you downloaded it to.
Type:
xmodmap colemak-lite.xmodmap
You might want to put this line in your .xinitrc (or whatever launches on startup)
Test results
I could, of course, show some results from the Keyboard Layout Analyzer, but I could just pick texts biased in my advantage. Let's try something interesting: use this code to load the layout yourself, and then share results from any text you want. This creates more variety in the texts picked, which gives a better insight.
Improvements
This layout is open for improvements, just remember that the main goal is to be more QWERTY-like. If you spot any keys that can be under the same finger (or even the same spot) as with QWERTY without too much sacrifice in CFU or finger travel, even if by rearranging some other keys, feel free to share. Constructive criticism is very welcome.