ARPIL has an additional library for a 3D particle system (which I am working on at Cateia at this very moment) which would be a nice addition to ARC. The good thing is that it poses almost no additional work for us, because I am currently finishing it up the engine as such and afterwards I'll finish integrating it into AprilUI (which can be optionally compiled with the "particle object" support). I suggest we keep this to ourselves and throw that in a special surprise. We can easily expose a few additional classes in the ARC module to have some additional control.
If you are curious, I am going to add aprilparticle as additional external library now so you can compile it in VS and check out the 2 demos. Particle definitions can be done directly (which usually creates a bunch of code) or simply through an XML file.
I was thinking how we are going to deliver the surprise. Basically we will after the full release of the new engine (not the RGSS clone) just make a few small scripts for starters where we will use the particle system to show off. People will be all like "WTF" and we'll be all like "Oh yeah. We didn't mention that ARC has a particle system. So now you know. :3"