I wouldn’t recommend this. While Classic II might be sound better than C214 (and definitely will sound different), it’s still quite similar to your C214: large-diaphragm condenser with high-frequency emphasis.
Why don’t you rather get something completely different:
- High-end small-diaphragm omni mike (DPA, Earthworks, …) These are great for acoustic instruments and vocals.
- High-end dynamic microphone (EV RE20, Sennheiser MD421, Shure SM7, …) These are great for amps and vocals.
You might even get one of each classes for a price of Classic II.