Hey there @CtrlAltDel
Sound Selection : It can fit the bill & the purpose for this kind of genre IMO ( pretending you're aiming at a more Hard Trance style than the original which is more in the subliminal Trance register ) but you're mainly using very sharp & transient driven sounds, it can sounds a bit harsh when the Mix gets busy and also over listening time since it's a rather long Mix ). You have nice atmosphere layers in the background, they could take more space in the Mix IMO. Bringing the piano is nice, it could perhaps also take more space by using more reverb & delay.
Arrangement wise : not sure if the long silence and the way you introduce the piano really works. Using reverb/delay with filters, you could keep that atmosphere background sound and some percussive elements to create a layer with the tail of those sounds. It's there but could be accentuated I think. More reverb on the piano and spreading it more in the stereo field might give another dimension to it, sounds a bit to dry and mono to me. Then around 4:07 after the break, the tack is loosing a lot of it's energy & punch. You just build tension before this, it should be the climax time IMO. That percussion sound doesn't fit right there, it's giving a kind of "loose" tempo at the wrong time : make this part sounds big !
Use of reverb & delays will definitely help to tame the harshness of those lead & synth sounds, the piano should really sound bigger.
Mixing wise, you could filter out some of the sub & low end, but the weakest point is the Kick. Looks like the punch of the kick is in the 70''ich freq. area, but the sub is really taking over, it's really making the kick thin, both in terms of level and presence/punch. The very transient driven bass doesn't help with that, you really need a more punchy & in your face kick IMO.
For compression & processing on your master rack, it's harder to judge by ears but it doesn't sound too much compressed to me.
And that's it for my 2 cents feedback, trying to be as much objective as possible since you know I'm more a fan of the more subliminal stuffs when it comes to Trance
Hope that helps