Can you post some links to these mods i'll check em out and see if it's possible to implement em in RO. You keep saying simple a lot and that TWI don't want to spend the time but if it's so simple why not try it yourself?
Infiltration, Serpentine, Nights Edge, Ballistic Weapons, all have features along thease lines using the Unreal engine, and the rest i know is possible because i do know a bit about Unreal tech.
But when i say "simple" it should be put into context, i mean "simple" for a veteran Dev team who has coded and animated stuff much more complex than this, but its not so simple for a newbie coder like me, which is why im not about to code it (well that, and it would require animation work too, and only a person who has the origional model files can pull that off, if it where only coded i might be able to mutate it, but its not).
Its all possible:
Toggle versus hold is natively supported, and Infiltration has used it since UT99, hell, that feature is at work every time you use the Lighning gun in regular UT, even Macro's are natively supported, as evidenced my the Adrenaline combos.
Over the sights aiming is easy, its just aiming, but lower the gun a bit, i have yet to see it done intentionally in an Unreal engine mod, but the tech is capable of it, you are just calling on different animations to be run, and we have seen that done a million times before, player models alone are infinately more complex than this.
Aim wobble is also possible, Serpentine was doing it in Unreal, Nights Edge in UT99, Inf and others aswell, and since models now have full skeletal animation, and you can assign shooting to a bone (the tip of the gun, so the shot goes where the gun is pointed without the need for complex code), it could actually be done just by animating it (but code would be better, so you could make it a bit random).
And ofcourse Ballstic Weapons for UT2k4 has done much much more complex stuff with aiming (even if it does rely on crosshairs) using a chaos system, and that one is coded much smarter than RO is (because its coded, not animated, you can tweak it at will, i suggest you look it over, its not realism as such, but it really shows what can be done), they even have weapon collision with the world Vietcong style (Inf has collision too, but their system is rather.. not user freindly).
Its all definately doable, and the code and animations required to do it is nowhere near as complex as other things RO allready has, so the Dev's should definately be capable of it.
But i dont think they want to, i have a feeling that they like it the way it is, and that RO wont see much more Dev time, afterall, they have to start on their next project at some point, and i think thats drawing ever nearer (but that is, admittedly, speculation on my part).