I haven't played the game too much yet, I'm going to keep playing, but one thing I love is the hold to click. I do agree with everyone else though, being able to bring the upgrades with us would make it feel like a smoother experience, but to balance this you can add faster scaling to the prices, making them cost more so you can't get too op. Great game in all though :)
Thank you so much for this feedback! If you're cool with checking back soon, we'll try out some updates and see if it helps. My dream is that the levelup doesn't feel punishing, but more like a breather. The later levels get very intense. But if the early stages of levels are too tedious, that's not ideal at all.