I like the controls, a bit awkward but if you could change your angle just a bit quicker, it'd good already, because I feel you'd be able to dodge some shots without needing the teleport with a bit more agility, allowing you to save teleport for when you really need it. I think it's more intuitive to press space again to teleport after you aim it, rather than having to left click, but that could be just me.
For the bosses, I think they lack a bit of gimmickery for their looks. Volcano and Ice are quite alike, in that they just spend most of the time shooting around themselves. Poison with the extra orbit guy changes it up, but I don't feel that as a poison planet. What I'd suggest are weaponizing your orbit and teleport system, and make these planets have AoEs around them that affect you if you're inside them, reducing where its safe to stand on your orbits, and asking you to teleport over it or face the consequences. Poison could have many gassy zones that fill up a poison condition, volcano could have hot zones that do damage as you step on them, ice could slow you down, so on.
Black hole was when it got interesting, with the reverse ring. Though when things come out of a black hole they come out as spaghetti, so maybe it'd be more clever to have it drawn in the round meteors and spit them out as spear-like projectiles. Maybe a phase 2 that spawns white holes around the arena and shoot these spears at you from all angles, evolving from the moon enemy you saw on poison boss.
And lastly, I think the range of your basic shot could be a bit bigger? I can see how it'd be awful for the game to just sniper elite your way through bosses, but you have to so upclose to shoot that depending on how your orbit is formatted, you can't hit for most of it, which I feel somewhat trivializes having the orbit control. Maybe balance it so more distant shots deal less damage, but do let you shoot from a bit farther.