If there's one thing I've learned about you recently CJ, it's that you have pretty good taste in classic games.
The synth choices as a whole are pretty basic. You need a much stronger bass synth (or dare I say, bass guitar?)
The thing I'm assuming people were referring to as the guitars... the midi things? There's a LOT of people you could probably get to play guitar for you. Try the recruitment forum! That would help fill out the soundscape a good bit.
The sequencing is very mechanical, and the source interpretation seems to be pretty conservative.. You should try some things to make it your own. Of course having live guitars could help with that. The synths would probably still be noticeable even if you had live guitars, but then you'd be able to say, "Oh that's intentional, this is inspired by 80s rock." You might even get away with it. *shrug*
The synths are pretty dry. I'm not saying to smother them with reverb and delay, but tasteful usage of reverb and delay can help a lot. The main thing though is trying to get the soundscape filled out for the most-part, and making the sequencing less mechanical. Fiddle with those velocities!
tl;dr Consider choosing more modern synths, apply effects where needed, get some live guitars, add velocities and other humanizing aspects to the sequencing..