I would just be happy if they created quill able whistles / horns, and had the engine and steam sounds ramp smoothly with speed instead of in noticeable increments (especially with steam). This would NOT require new sound recordings and engineers.
When I've asked about this, I get "oh that's difficult and not capable in the sound engine". Translation: "We're too darn lazy to rewrite the code so live with it". Having a friend that been a game developer for years and who is now a senior project manager, he's basically told me the same thing when asked about these kinds of issues- they're making excuses, probably because they coded themselves into a corner and don't want to do the work required to rebuild the code.
When you consider that the sound on my MTH and Lionel locomotives can do this, and do it convincingly, with a small sound chip, and N3V has access to all the power of a sound card in a PC, their "reasons" for not doing this are laughable.