Wow, okay, this is going to be alot, you may not understand everything, so ask questions.
The first song isn't brickwall limited, you only have one limiter, the "up and down" he hears is due to the snare. The snare overrides the sounds of the other synths ,chords, pads, whatever you have in there, for a short period of time, and it causes a "bouncy" type of rhythm, notice that when the drums speed up at 00:42-00:47 that there is none of this "bouncy" business. The other thing is probably the bass he hears. the reason for that sounding high then low is due to simple level changes I presume? different octaves to produce melody, yes? but it is kinda hard to hear, and the lead synths or chords are simply too loud. The lead synth is supposed to lead you in, you kind of start off with just all the chords and the synth, maybe just take a few out, then as the song progresses you can start putting them in, not all at once, but if you know nothing of music theory, then just do what sounds best. the bass in the beginning is just way too overpowering, I mistook that for a synth or chord. The lead synth should be alone in the beginning, accompanying sounds just defeat the purpose of a lead synth. let the synth lead in, then at about 7 seconds after it's melody is complete and begins anew, bring in the bass, but not too overpowering. Keep the chords slight in the beginning or whatever you are using other than the synth and bass, then as the melody of the lead begins again, start bringing in more of the chords or pads, etc. then second completed melody is perfect when you bring in the snare and hats, and begin to modulate the bass, which is the overall sequence of it. The first 40 seconds seem kind of dull. Try adding a little more sounds to construct it's progression, just so people aren't listening to the same thing for about 40 seconds. And try a little variation in the melodies, just the same melody can get kind of boring. Just experiment.
DON'T erase everything, that would be a waste, just try a little more construction and progression.
Bear with me here, we have 3 more songs to go.
the second songs opening could be a little longer, just try to add progression, i only heard 3 sounds in there. the kick sounds like it's missing something, try adding like a small bass under it, just to make it sound a little heavier. just to give the listener that "incoming" type feeling. Also, the kick seem a little rushed, not really a quickening up feeling to it. that noise right at the beginning of the chords seemed miss placed try adding near the middle of the progression and then breaking it at the start of the chords and let it fade.the chords at 1:44.5-1:46.5 were way out of harmony, try bringing it down a level or try coordinating it a bit more. The drop at 1:48.5 through the rest of it's duration seems pretty good. the beat could use more variation other than just 1,2,1,2. You might think, "well who the hell is going to listen to that?" quite a few do as a matter of fact. the ending to it was perfect, don't change that. during the overall drop you might want to add an underlying synth so it adds to the fullness of it, because with out the chords it's just the beat and the noises. all within harmony of course, don't just throw shit in there. Overall pretty good, keep it up man

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A shorter one now

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The opening pretty well made, couldn't really find anything wrong with it. The kicks actually sound pretty good in there too, so nothing to say there. the "duck" or whatever it may be called is perfectly fine, rather than take it out, build it up. maybe add an "are you ready voice" or something, pretty sure there is a sample or two out there. to build it up just experiment with a heavy bass under the kicks and in between and speed up the kicks a little, add the "incoming feeling to it, because the "duck" is usually followed by intense build, especially in the middle of a song, make the listener fall with the song, build them up high, then drop then and catch them in the middle of it. no need to change it's location or the rate at which it returns to normal, perfectly fine there. defiantly a pretty good song.
Last one :D!
This last one is awesomely progressed, the kicks might need to be a little, just a little softer when it's alone with the piano melody, bass, chords, and clap,same with the bass, just a little lower and it'll be perfect, just so we can hear the chords a little more, or you can just increase those a little, but when those other chords come in, or lead synths, whatever they maybe , it's pretty much perfect. but I do stress repetition, it sounds like it is going to have alot of it, just keep things interesting, don't hold notes longer than they should be held, don't stay on the same octave too long and at 4:32 it sounded like those chords or synths were going to go back to the same octave after they descended a little, try putting them on a the very next lower octave, i'm going from my ears on this one, so it may sound like shit. try it, adjust things a little if needed and see how it sounds, if you rather not then that's okay, it's just an idea.
Phew, that took alot of listening and typing. please take what I have to say into consideration, you asked for advice so please take some and don't just blow off because it looks like a fucking essay. Overall dude, great tracks, looking forward to this episode of yours, keep it up and never give up

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