First of all welcome to Sonic Academy & the Forums, hope you'll enjoy it, there's always a bunch of stuff to learn here, even for seasoned or experienced producers
That's a lot of questions in one topic... Lol but they are related so I will try to provide some general answers.
I think too, because the track is full, covering a good frequency range and you've got enough elements in it, so I personally won't add more.
Now, the simple answer is in your first comment. If you're happy with the track and if you're not 100% sure that you could/should make it better, then the track is probably finished. It's the terrible question that many producers will struggle to answer anyway, some would reply that a track is never finished & it's true that the more you'll be listening to it & thinking about adding this or that, it could never ends and then you'll never finish the track for sure. So at a certain point you have to decide that it's finished & ready to go out there.
Well it matches your song title so far, so ?? So if you decide to get rid off it, that might be changed too. I think that it sits well in the track but it could be more Fx processed maybe, making it a bit more dark/weird/spacey ?? Again that's very personal & depending of what you want to deliver to your audience, in this case a vocal phrase related to the track's title makes sense.
Of course if you want your music to have a chance to be released & if you are ready to sign a contract with a Label which is a topic on its own... There's a "pinned" topic on the forums about it https://forums.sonicacademy.com/t/label-information/
I won't recommend any particular Label here on the Forums, you have to aim at the ones that are preferably matching your genre of music and well established & serious ( because there's a lot of disappointing adventure with Labels never releasing your track, contracts & so on... ). So it's something to take seriously and you need to spend a good amount of time grabbing information about that.
Next to that there are other ways to make your music available to the world and to promote it as well as getting benefits & royalties out of it. Digital Medias Delivery Services are now playing a huge role in music distribution and getting your music on Spotify, Apple Music/iTunes, Deezer, Beatport... ( the list is huge !! ) can now be done by subscribing to a medias delivery service and paying a fee per track, per albums, even unlimited. Of course those services are more or less expensive & efficient, they will keep a certain percentage of your royalties, so it's another full topic as well as another "jungle" to explore, take the time for it. Some platforms will even offer you Mastering Online features by running your tracks via online elaborates algorithms ) and Digital Delivery at the same time ( which I'll talk later to answer your last question ).
And to finish with what's available on the Web, there are also services aiming at helping you finding Labels or Pitching your tracks to make them heard by Labels or getting "briefs" opportunities. Some of the popular ones being https://www.submithub.com/ and also https://www.musicgateway.com/
Of course do not forget that the music industry is a business & since the emergence of Digital Medias & possible revenues opportunities you'll find goods & evils on the web, so again take the time to explore.
Next to that, don't forget the more direct & even the physical contact network. You could kindly ask Dj's if they would play your track in their sets via Social Medias Hubs or directly if you know any ( even locally, the goal is to make your music heard ). Trying to make a physical & personal connection with Labels or famous Dj's ( preferably Dj's running a Label , lol ) is also something to try : think about the story of Skrillex daring to put his nose in front of Deadmau5 & hanging him a usb key with his music on it : well it ends up as Skrillex selling more music than Deadmau5 !!
Same stories as for Labels & Digital Delivery Companies, preferably aiming for some established ones and specialized in your genre or at least EDM ( you're not going to give this track to Hans Zimmer, right ?? ) and again you'll find a bunch of offers on the Web, more or less pricey & serious : another jungle, there's no secret nowadays, you need to think twice about it and to spend time to research, that's also where physical connections into the music world is very handy.
As mentioned before, you can now master your tracks online and some companies even offer to digitally distribute your tracks, LANDR is one of them among others.
Mixing with Ozone 8 is already great and you could have a very decent Pre-mastered track using it, some even achieve to fully master their tracks. Next to that, their are other plugins viewed as invaluable tools to help you get your tracks ready to be delivered on digital medias, in my opinion Nugen Audio MasterCheck Pro is one of the best.
You have a very good track ( in my opinion, as said I will maybe tweak the vocals a bit, that's all ) but yes, it needs mastering to compete with standards but one could achieve valuable mastering results "in the box" if you wish to digg further into that part of course, because many producers don't like it that much and prefer to pay for that tedious part of music production, it's another world behind creativity.
This is very generic information of course, but I hope you'll find it informative enough. Also, there's a search function on the Forums ( magnify icon left to the menu on the top bar ) so feel free to perform a search with worlds like "Labels"...etc.