Yeah, I really agree that it quickly feels like once you've seen one planet of a given type (or two, or five, or ten, or...) you've seen them all. I feel like the game might benefit from more information about what's on a planet EG "civilization detected" or "Avian Temple Detected", based on upgrades or spent resources on a sensor item. It also feels like it needs a campaign that actually justifies the huge galaxy map, something like Star Control where different regions are populated by friendly or hostile aliens, or maybe if there were hints, puzzles and riddles that would lead you towards difficult dungeons with equipment/quest items. Or maybe something where you invade planets, and defend against invaders? I guess that's getting kind of far from the original vision. Maybe it just needs more handcrafted scenarios (currently there are four in the game, plus another half dozen or dozen worth of good dungeons). Maybe it needs PvP. But, it needs SOMETHING more.
Mind you, I'm not done with the game. I want to get my fully upgraded ship, see all the powers, gather my favorite decorations, and maybe build a cool structure or two on a server where people can see them, if they ever come on. Right now I'm just searching for the quest items I need to level up and... it feels exactly like killing monsters over and over for a rare drop in an MMO. I intend to catalog every quest item in my 3D printer if I can, just so I can help other people skip through the quests. Now where's that damnable golden ducky...