Thanks for the comments - just so we are clear, I wouldn't want to 'release' any of the sounds in these videos, some are okay but they are very much just sketches. It's difficult to know what direction to take at this stage, I want the character of the sounds to remain in-tact but that might be difficult because overall I want the game to sound much cleaner, in some cases this means toning down some of the sounds and making them lighter.
The old sounds are 8bit - this means that the sound designer would have made every sound as loud as possible to reduce the signal to noise ratio, as a result the sound design lack subtlety. It's here where I'll be taking artistic license - on an individual level the sounds may or not sound close to the originals but as a whole being played together they should work well with each other and still keep the style which FS2 adopted which are quite Earthy sounds based on Jets and modern war machines as well as synths and effects.
To re-iterate one simple bit of functionality which will improve this project by 1000% would be support for sound variations - instead of just one wasp missile launch sound I want the game to pick from 20 of them. 
...sounds probably shouldn't deviate too much from the originals... it needs to be a clear upgrade, it needs to be recognizable as the original.
I've been working on Runescape for a year modernizing 10 years old audio (to the limitations of the audio engine). One thing I've come up against is that some older players will grate against any sort of change to the sounds. For the reasons mentioned above I'm just going to work towards how I feel the game would sound today but still trying to maintain the character of the originals.
That said if people want to use any of the sounds which more closely resemble the originals officially then they're welcome to.
... but I really don't like the BVas sound. You should keep the high-pitched screeching character of the original beams...
Yeah I totally agree -this was the last thing I did last night, hearing it again this morning I think it sounds awful haha.
...if that was a subspace sound I heard in the second video...
No I didn't touch that - there's a few sounds which are intimidating (in a fun way) because they are so iconic - the beam laser and subspace sounds are two of them.

On-topic: What would your take on the interface sounds be, mkmanner?
All the UI sounds like missile warnings, lock-ons etc I think need a bit of a facelift, much like the rest of the game they are very heavy and thick - I think for these sort of sounds you need something that can be heard very clearly but has a frequency range which doesn't completely dominate the mix.