I found the emulationstation-dev branch to be a bit unstable for my likings. For some reason, that build of Emulationstation causes an error with the ALSA sound driver that I wasn't able to resolve. Reverting back to the default build of emulationstation eliminated the error.
So, I had to come up with a bit of a compromise for sorting. I was able to address alpha/numeric ordering (e.g. 1, II, 3 instead of 1, 3, II) by using a strategically placed, non-visible "zero-width space" character (​). For example, the <name> text for the Mortal Kombat arcade games might be:
<name>Mortal Kombat</name>
<name>Mortal Kombat II</name>
<name>Mortal Kombat ​3</name>
The zero-width space HTML entity will not render in the UI of Emulationstation and it's ASCII value is greater than an alphanumeric character. So, when sorting alphabetically, this eliminates the MK, MK3, MKII issue and correctly moves MK3 after MKII.
This character can be used multiple times and in other scenarios, such as ensuring "Leisure Suit Larry in The Land of the Lounge Lizards" (LSL1) gets sorted before "Leisure Suit Larry Goes Looking for Love (In Several Wrong Places)" (LSL2). The word "in" can be sorted before the word "goes" by using this method. It also allows somewhat arbitrary sorting.
I'm not sure how this affects other areas of Emulationstation. I just know that it is an alternative. One downside is not being able to easily handle sorting articles in the title, such as The and A. Using this zero-width space character at the beginning of every title would be cumbersome and difficult to maintain.
