Weird question about creating game-specific menus in EmulationStation

[Ikyrus]

So I had this idea that I'd like t o create a few menus in EmulationStation for specific game series. For example, if I wanted to put every CastleVania game (from all the different systems it has had iterations on) into one CastleVania menu. Now I know I could put all the CastleVania games into their own ROM folder and create an entry in the es_systems.cfg pointing to it and have it recognize all of the necessary extensions and then add all of the appropriate emulators to the emulators.cfg file in a matching config folder.

BUT...

I would like to also have the different CastleVania games appear in their respective console menus, as well, without having separate instances of the ROMs (having, say, two copies of Dracula X Chronicles for PSP would take a heafty amount of space on the SD Card). So basically I want two different menus to point to the same ROM file.

My question is two-part:

1. Can you create a path in an es_systems.cfg entry that links directly to a particular ROM?

Example:
<path>/home/pi/RetroPie/roms/castlevania/castlevania 2.nes</path>

2. Failing that, if I put all of the CastleVania games into their own folder could I then add multiple ROM paths to the existing entries in es_systems.cfg?

Example:
<system>
<name>nes</name>
<fullname>Nintendo Entertainment System</fullname>
<path>/home/pi/RetroPie/roms/nes</path>
<path>/home/pi/RetroPie/roms/castlevania</path>
<extension>.nes .zip .NES .ZIP</extension>
<command>/opt/retropie/supplementary/runcommand/runcommand.sh 0 SYS nes %ROM%</command>
<platform>nes</platform>
<theme>nes</theme>
</system>

I understand this may just not be doable, at least in the manner I desire, but I thought I'd ask before I go monkeying. I am also open to any alternative solutions. Thanks!