I really was impressed with the "point to go to" effect. It seemed like it would only teleport me when it determined that there was a place for me to land, which was surprisingly effective. It felt like it had a certain freedom to it... it actually kind of reminds me of how a lot of devs (when showing off fancy open world games now) will say something like "see those mountains back there? You can go to those". Your game kind of takes that and says... you can go there... right now... ziiiiip *standing on mountain*.
I have to say though that I kind of wish you included more areas you could explore locally. Sometimes while exploring the city/tower areas I would jump from the top of one tower down to another, then spot a good teleport location... jump of the current place, and while mid-air use my teleporter to zip off somewhere else not to far off. There isn't really a sense of gravity or intensity to the falling portion though, so it felt a bit less... cool. I think you really missed an opportunity relying so heavily on the teleporter to move around. Some local platforms to jump around to and find things would have really helped break up some of the monotony that comes with having to precisely line up each "shot" from a distance.
So yeah, so windy "falling sound" fading in, a bit of screen wobble increase as you fall would have really helped with the immersive quality of falling. Then constructing areas that were designed to be teleported to and navigated by jumping mostly without the device would have helped break up the pacing a bit.
I also found the overall objective to be pretty uninteresting, and there were a lot of things I felt were added to just kind of extend gameplay in uninteresting ways. Collecting things just felt like a chore, and I grew tired of that design very quickly. After that decided I just wanted to use the teleport gun until I felt I explored its uses enough. This is where I started experimenting with jumping around the city's geometry, and it was somewhat entertaining for a little bit but also grew dull fairly quickly. Basically, by the time I was anywhere near any collectibles, I had already started to grow tired of the normal "point to go to" mechanic. Everything felt incredibly stretched out, even things like the intro staircase were absurdly long and tedious. It seemed like at some point you felt you didn't have enough content, so in order to remedy that the idea was to duplicate stuff and stretch it out further. That may not have been how the process actually went, but it's how it felt as a player. The whole thing felt a bit "samey" after a while.
I'd recommend putting things a bit further together, removing some of the content that feels unnecessary, and make the parts that are there interesting to explore. The city structures for instance, while interesting at first, felt completely hollow. They were massive but the had little of interest to actually explore or to take interest in. That's kind of how the whole game felt after a while, massive, awe inspiring... but ultimately hollow.
You've got a very solid mechanic here that's incredibly intriguing and very different in terms of navigating a space. The main thing is making that space interesting. After I jumped to a couple of those purple cube platforms and never found anything of interest at them I stopped teleporting to them when I could. They weren't interesting to visit. The same thing happened with the city areas.
Aside from the gameplay becoming tedious for me, I found the audio and general mood to be pleasing. Seeing the cities off in the distance and the yearning to see them up close had a sense of scale and intrigue that's hard to achieve for most games. It's all the things in between that were missing. The journey was completely lackluster, and the payoff for making it was a disappointment.
Also, I think you've got some sort of bug with the npc movement. They all seem to move as if they are reacting to the player input for moving forward. That was a bit odd, unless it's symbolic or something...
I don't want to come across like I didn't like it. I just found it sort of frustrating that such an interesting mechanic because so bogged down with tedium. In order to improve it, I'd recommend taking what you enjoy about the experience and refining and improving those aspects while removing things that come across as being unnecessary.
For me personally, that would mean removing half the platforms. Creating medium-sized areas that are enjoyable to traverse with a mixture of player jumping and the gun usage... and polishing that up until it was purely enjoyable just to navigate different spaces. No collectables, perhaps leave an ambiguous narrative but keep it mysterious... and also personally an emphasis on sound design. Footsteps, sounds for jumping, falling, additional ambient sounds for areas you're around, wind for open places, muffled interior sounds for... interiors. You get the picture.
https://www.freesound.org/ is a good resource for sounds.