1. The speed that radiation rises does actually increase as the game progress, although very gradually. Either way, I think the premise of the core going "out of control" is enough to fit the theme, although maybe not too strictly.
2. I think this is a fair point, especially for the fishing minigame. It's more difficult and easier to fail than the other games, so giving you more time would be better.
3. The game doesn't end, although since the time you have left decreases over time, you'll eventually reach a kill-screen.
4. I unfortunately didn't have time to add any in-game instructions or a main menu. The game is pretty small and fast-paced, so hopefully just playing each minigame once or twice is enough to understand everything.
I did have some more minigames planned which I didn't have time to include. I might go back and add those in later, although I'm not sure if I can do that during the rating period. Thanks for the constructive criticism. I'll play your game as well.