Thank you for playing, the kind words, and the feedback.
We agree that the early game is a bit too tough, especially for a jam game. We made some late changes, and focused more on balancing them for the mid-game, which negatively impacted the early game. Our post-jam update will lower some initial costs, and add highlighting of some recommended initial upgrades.
We did want to get more SFX, but did not get around to it. There will be a ship explosion VFX added in the post-jam update, though not sure if we will get to more SFX as well. If we continue work in the future, there will be more SFX and VFX added.