If I had to get picky, this is my Simon Cowell-ish style feedback.
Overall, your electronica stuff is all really nice, some of it is a bit safe and standard, but well done. Some if it just needs a second listen, which is why you are smart enough to push for feedback from us.
1)
Retro Trance Instrumental - Lovely piano intro, love it and the bleepy stinger that begins the synth whistle is great. The overdriven bass is ok, would perfer something smoother. My biggest problem with this track is I really don't care for the tone of the synth whistle main melody at all. It's a bit like an annoying cousin who whistles when he's doing chores and you just kind of want to smack him. I'd suggest finding a different instrument for this melody, because it is good, I just don't like that instrument. It is also a bit too loud in the mix. The techno part is fine also. The "loud soft loud" is nicely done in this track, but the loud could be toned down a bit.
2)
Electro-Funk Instrumental - Starts nice, I love the mellow soft tones. The bass-line that comes in and the one two drum is great. The synth elements are also nice. Not a big fan of the metal drums type sections, I wish it didn't have those parts and stayed kind of mellow and loung-ey. I'd prefer to hear a smooth, soulful solo or bridge to that double-time type element.
3)
Symphonic/Electronic Hybrid Pop Instrumental - This is ok, it's a nice progressive theme. But it starts out a little annoyingly, with what sounds like someone holding a tambourine while having a grand-mals seizure for the first 30 seconds (which comes back again later. It may be that I'm just not a fan of this sample used in this way for the lengths that it is used in this piece. I like the fuzzy bass a lot and the whirling part at the end around the 3:15 mark is great. This composition has promise, it is a bit long for it's repetitiveness to carry it on it's own. It could use a stronger variation bridge.
Keep up the good work and consider making some more colorful track names. Feel free to hit me up for more feedback in the future and I'd love to hear your revisions of these.