Short answer: a pair of SDCs would provide
dramatic improvements in your recordings, far more than any other piece of gear and/or a different single-point stereo mic.
Long answer:
I know you said you like gear that's minimal and easy & quick to set up*, but I strongly recommend considering a pair of SDCs. A modular system would prove ideal, allowing you to switch between cardioids or omnis (or even hypercardioids) for different recording environments, but even a pair of fixed cardioids would produce big improvements. Using a pair of mics would allow you to use a variety of coincident and near-coincident mic configurations, instead of the single fixed, coincident configuration of a single-point stereo mic.
The ability to change the included angle alone, even if still running a coincident configuration, would have a significant impact. But running
near-coincident mic configurations would deliver even larger improvements. The primary benefits of running near-coincident configurations:
- Time-difference stereo. Coincident configurations provide intensity-difference stereo. Near-coincident configurations provide intensity- and time-difference stereo. Generally, and all else being equal (e.g. stereo recording angle), mic configurations with time-difference stereo produce what some might call a greater sense of space.
- Flexibility and control. Due to the ability to change not only included angle, but also spacing, you have far greater flexibility in controlling the sound of the recording. You can change the configuration to control the stereo recording angle and, to a significant degree, the relative levels of direct and reverberant sound captured by both mics. All else being equal (like stereo recording angle)...want to capture less reverberant (i.e. "room") sound? Try wider spacing with narrower included angle. Think the room sounds great and want to capture more of the "room" sound? Reduce spacing and increase the included angle.
* It's not much more hassle to set up a pair of mics, and IMO the benefits greatly outweigh the additional hassle. And there are ways you can streamline the setup, e.g. leave the mic bar and/or shockmounts on the stand. The AKG KM 235 stereo bar is great in this regard because it allows one to fold the bar towards the center of the stand to minimize the on-stand footprint of the shockmounts and mount bar for transport.