This is a great question! There's a myriad of ways to get your new, unheard music out to the masses. In addition to the two you mentioned, Spotify is one of my personal favorite ways to discover new music, so if you aren't already on there I would highly recommend it. However, let's think beyond those kinds of platforms for a moment and focus on three that I believe are the strongest for new discovery.
You've heard this before, right? But that's because it's crucial to a budding musician's career. Learning to use your social media to your advantage will give your music a huge boost. This means posting daily, and posting engaging content that follows the 70-20-10 rule (look this up if you aren't familiar—it's worth it). Keep in mind that your goal with social media is to build your brand and trust that the fans will come naturally from that, a few ways to do this include: sharing behind the scenes photos, fun facts about the song/video/recording process, asking fans what their favorite lyric is, posting a relatable lyric from the song on a graphic and sharing that. These are just a few ways to get started!
Blogs are still one of the top ways that people discover new indie artists. If you don't have the relationships or time to build the relationships yourself, I highly suggest hiring a publicist for this one, because cold emailing will almost never work. If you are going to hire a publicist, know that most publicists only work with music that is either unreleased (so they can set up a premiere partner and promote from there) or that is released within the last month. After that, getting blog placement becomes difficult.
You know when you're watching TV and hear a really rad song in the background of a commercial or TV show or movie? That's the result of licensing, and it has given a LOT of bands their big break. Now, sometimes your music will get placed and it won't boost you to superstar success but it WILL give you more visibility and a bit of cash in your pocket.There are a LOT of articles out there that will help get you set up in licensing, so I'll just leave you with this: licensing is one of the easier ways to get your music into the spotlight and while there's no guarantee, there's also really no downside.