This game could use a "city wish list" to see the item categories your mates need. Like, I need spears right now. Any spear would do lol. Just to keep them from getting angry!
If you're looking for an easy 500,000 (or heck, 1 million) distance, just change all your followers to launch power and total objects. Mine were about 50/50 on those two stats. Then, with 3-4 perfect power generators, launch at 30-40 degree incline to hit balloons constantly. Launching at 60 degrees is undesirable because you hit less balloons by going slower and having steeper ascent and decent angles.
Doing this, you'll get 500,000 with zero rocket used. Probably 1 million with zero rocket used.
If you're going for the hard badge, unlock the "all splitters" and "all ghosts". These are super easy modes to get more levels completed. For splitters, just have 4 AOE towers. For ghosts, have 3 Ghost Burst and however many plain ghost towers you feel like. You can send 20 waves at a time with these two modes.
Puzzles got boring for me around 26. The solutions are obvious and the punishment for getting screwed over by the crappy controls are immense due to the ratio between completion time and thinking time.
Can't click and drag the tutorial green line. I can click and drag the guy on the screen, but he doesn't do anything. I play in firefox zoomed in so the game fills the screen.
Ugh, how depressing. The difference between first time and successive tries is insane. Even with all the developer updates from the "best comments" it's still a GRIND. If I wanted to grind I'd pay Blizzard $15 a month.
Mechanics and gameplay just are not there. For a game like this, the pause after hitting a wall before he sticks and the pause after landing before he can roll are just astoundingly aggravating.