Adding my own, thanks @Mark for encouragement.

Xah Fly Keys

Designed from the ground up for emacs, with the goal of being the MOST efficient system, from years experience with ergoemacs-mode. Key choices are science based as much as possible, based on statistics of key frequency and key easy-to-press score. Most frequently used commands are mapped to the most easy-to-press keys. Other issues, such as grouping, and keybinding bigram, are also considered from 3 years of weekly experiment.

Interesting Points:

• All C-x commands are done by sequence of 2 to 3 single keys. In xah-fly-keys, C-x is never necessary. M- is never necessary neither.
• Does not conflict with any GNU emacs's keys, because it does not bind Ctrl or Meta (except C-7, C-8, but not essential). You can have xah-fly-keys on in insert mode, and use GNU Emacs the way you normally do.
• Also considered what set of commands results in max editing efficiency. So, the package uses ~80 custom editing commands. (for example, copy will copy current line if there's no selection. One single command to toggle letter case, instead of GNU Emacs's ~6 variations of upper/lower/region/no-region.)
• The implementation is as simple as possible. No macro, no advice, no complex remapping of keys, only a couple hooks are used. (good or bad?!)

Disadvantages:

• Like learning vi for the first time, you'll need one month to adopt.
• Not well known. Just released for public use this month.
• Currently support Dvorak layout only.
• No convenient key diagram for learning (yet).
• For major modes, you still need to use C-c. (so, you might use other packages such as god-mode or hydra to solve this problem.)

I'm the author, so be warned that I may be unconciously biased. Feel free to comment or correct.

Adding my own, thanks @Mark for encouragement.

Xah Fly Keys

Designed from the ground up for emacs, with the goal of being the MOST efficient system, from years experience with ergoemacs-mode. Key choices are science based as much as possible, based on statistics of key frequency and key easy-to-press score. Most frequently used commands are mapped to the most easy-to-press keys. Other issues, such as grouping, and keybinding bigram, are also considered from 3 years of weekly experiment.

Interesting Points:

• All C-x commands are done by sequence of 2 to 3 single keys. In xah-fly-keys, C-x is never necessary. M- is never necessary neither.
• Does not conflict with any GNU emacs's keys, because it does not bind Ctrl or Meta (except C-7, C-8, but not essential). You can have xah-fly-keys on in insert mode, and use GNU Emacs the way you normally do.
• Also considered what set of commands results in max editing efficiency. So, the package uses ~80 custom editing commands. (for example, copy will copy current line if there's no selection. One single command to toggle letter case, instead of GNU Emacs's ~6 variations of upper/lower/region/no-region.)
• The implementation is as simple as possible. No macro, no advice, no complex remapping of keys, only a couple hooks are used. (good or bad?!)
• Supports over 10 keyboard layouts, including: QWERTY, dvorak, colemak, colemak-mod-dh, qwerty-abnt, qwertz, azerty, programer-dvorak, workman, norman.

Disadvantages:

• Like learning vi for the first time, you'll need one month to adopt.
• Less well known than evil-mode.
• For major modes, you still need to use C-c. (so, you might use other packages such as god-mode or hydra to solve this problem.)

I'm the author, so be warned that I may be unconsciously biased. Feel free to comment or correct.

Adding my own, thanks @Mark for encouragement.

Xah Fly Keys

Designed from the ground up for emacs, with the goal of being the MOST efficient system, from years experience with ergoemacs-mode. Key choices are science based as much as possible, based on statics of key frequency and key easy-to-press score. Most frequently used commands are mapped to the most easy-to-press keys. Other issues, such as grouping, and keybinding bigram, are also considered from 3 years of weekly experiment.

Interesting Points:

• All C-x commands are done by sequence of 2 to 3 single keys. In xah-fly-keys, C-x is never necessary. M- is never necessary neither.
• Does not conflict with any GNU emacs's keys, because it does not bind Ctrl or Meta (except C-7, C-8, but not essential). You can have xah-fly-keys on in insert mode, and use GNU Emacs the way you normally do.
• Also considered what set of commands results in max editing efficiency. So, the package uses ~80 custom editing commands. (for example, copy will copy current line if there's no selection. One single command to toggle letter case, instead of GNU Emacs's ~6 variations of upper/lower/region/no-region.)
• The implementation is as simple as possible. No macro, no advice, no complex remapping of keys, only a couple hooks are used. (good or bad?!)

Disadvantages:

• Like learning vi for the first time, you'll need one month to adopt.
• Not well known. Just released for public use this month.
• Currently support Dvorak layout only.
• No convenient key diagram for learning (yet).
• For major modes, you still need to use C-c. (so, you might use other packages such as god-mode or hydra to solve this problem.)

I'm the author, so be warned that I may be unconciously biased. Feel free to comment or correct.

Adding my own, thanks @Mark for encouragement.

Xah Fly Keys

Designed from the ground up for emacs, with the goal of being the MOST efficient system, from years experience with ergoemacs-mode. Key choices are science based as much as possible, based on statistics of key frequency and key easy-to-press score. Most frequently used commands are mapped to the most easy-to-press keys. Other issues, such as grouping, and keybinding bigram, are also considered from 3 years of weekly experiment.

Interesting Points:

• All C-x commands are done by sequence of 2 to 3 single keys. In xah-fly-keys, C-x is never necessary. M- is never necessary neither.
• Does not conflict with any GNU emacs's keys, because it does not bind Ctrl or Meta (except C-7, C-8, but not essential). You can have xah-fly-keys on in insert mode, and use GNU Emacs the way you normally do.
• Also considered what set of commands results in max editing efficiency. So, the package uses ~80 custom editing commands. (for example, copy will copy current line if there's no selection. One single command to toggle letter case, instead of GNU Emacs's ~6 variations of upper/lower/region/no-region.)
• The implementation is as simple as possible. No macro, no advice, no complex remapping of keys, only a couple hooks are used. (good or bad?!)

Disadvantages:

• Like learning vi for the first time, you'll need one month to adopt.
• Not well known. Just released for public use this month.
• Currently support Dvorak layout only.
• No convenient key diagram for learning (yet).
• For major modes, you still need to use C-c. (so, you might use other packages such as god-mode or hydra to solve this problem.)

I'm the author, so be warned that I may be unconciously biased. Feel free to comment or correct.