The thing to understand is that there are different ways to make sound and that each card (apart from the very oldest) combine several of them to differing degrees of quality and compatibility. The fact that there are multiple new sound cards based on different chips and designs being made in the retro community proves there is no single "best at everything" card.
That said, the MK8330 ticks just about all the boxes:
- 1:1 OPL3 clone for FM synthesis ("AdLib")
- Soundblaster & Soundblaster Pro 2 support
- Soundblaster 16 support, including high DMA channel
- WSS support (although I'm not aware of any games that offer WSS that do not also offer SB16)
- bug-free MPU-401 UART MIDI for waveblaster daughterboards or external MIDI modules
- SPDIF digital output
- modern enthousiast-level design for low analog noise levels
Apart from the last point, this is all courtesy of the C-Media CMI8330 chip, which was a very late ISA design used back in the day on some awfully low-end cards and motherboards. I've only used mine a little bit, but it seems to do everything it should. I was previously a fan of the AudioExcel AV310 card with this same chip, and used that in my main DOS system a lot. The only compatibility issue I ever encountered was that I couldn't get digital audio in Ultima 7, but that is about the worst possible game to get working properly. I only ever succeeded with my Snark Barker, a 1:1 replica of the Sound Blaster 1.0.
The only other chip to offer similar feature set to the CMI8330 (just no SPDIF) is the Avance Logic ALS100 (non-plus!), a slightly older design, suffering from the same lack of good quality cards..
By comparison, the 'real' Soundblaster 16 cards all have some kind of MIDI bug (the AWE64 only has slowdowns when also playing 16b audio, anything older has some degree of hanging notes), they don't support WSS, newer ones have good noise levels, but no real-sounding OPL3 for FM, older ones have real OPL3 but frequently bad noise levels.
Reality-check though: by far the most DOS games that say "Soundblaster 16" still only use 8b 22kHz audio, and a lot of the ones that actually do use 16b audio also support WSS. That means that SB16 support is actually not that important in most cases. In that case there's a huge range of acceptable chips/cards with Aztech (AZT2316 and AZT2320) and OPTi (929 and 930) chipsets that offer real OPL3, SBPro2, WSS and bug-free MIDI and can be found pretty cheaply. I personally prefer the Aztech cards & chips, but others tend more towards OPTi, but they are very similar overall.
Now, focusing on your use cases:
DOS: see the mess above 😉
Win3.x: WSS is the relevant spec here, although anything with Win3.x drivers will basically work. Win3.x also has excellent MIDI support.
Star Trek A Final Unity:
This is a fun one - a 1993 game released in 1995, and it shows in the supported cards list; Ensoniq Soundscape, Gravis Ultrasound / ACE, Pro Audio Spectrum, Sound Blaster, Sound Blaster 16, Sound Blaster Pro. If you balk at Sound Blasters around USD 90-100, Soundscape and GUS are completely out of the question. Pro Audio Spectrum has some of the best 16b audio out there, but not much supports it, and its Sound Blaster support is just Sound Blaster (non-Pro, non-16), so no good as a 'jack of all trades' card. That leaves you SB16 or SBPro. If the game actually uses 16b audio, then that's a must-have for you, particularly if you remember running it with SB16 back in the day. If not, well, any SBpro-compatible would do the trick. I've not been able to find out what audio quality it uses.
Tbh, based on this - WSS nice-to-have for Win3.x and SB16 needed for best (affordable) Final Unity experience - either the ALS100 or CMI8330 still sound like the best single-card options, and the MK8330 is undoubtedly the best card with either chipset. If that's too expensive, look at anything else with those chipsets that fits your budget (just avoid the ALS100plus+ - as it lacks high DMA support for SB16).
