One feature I have asked for in the past is the ability to add an EFX to ALL clips in a layer that would apply AFTER the EFX applied to an individual clip. That could easily be accomplished (at least in the interface) with R2 by making the global EFX "layer specific" - that is, have an EFX in one of the 3 global slots apply only to the corresponding layer (1, 2 or 3) before it is composited with other layers. Any EFX in the global slots that are not "layer specific" would still be global.
In version 3 you will be able to put FX on a clip, layer or global. When a FX is applied to a layer all clips played in that layer will have this effect applied after their own FX. So just how you want it
Mixing in images could be considered a special case of all the other mixing modes. Image display and pan/zoom in R2 is very jerky and usually requires pre-rendering in After Effects. Being able to smoothly scroll images in a given layer would be really nice. Also being able to handle transitions between a sequence of images with various dissolves or wipes would be great.
Each clip has properties like position, rotation and scale. So you can easily zoom and pan each clip without having to apply specific FX's. There is no functionality to use various dissolves and wipes when running a sequence of images though.