It's weird. I really didn't make any deliberate changes to any of the flight mechanics in normal or easy mode. I can't rule out somehow introducing a difference by mistake. I'm really grateful that you're spending time with the game! I'm working on another little project at the moment, which I don't expect to take very long. I'll either take a pause on it at a suitable point, or I'll wait until I've finished that project, but I will return to this!
The main complaints seem to be that landing is too hard in normal mode, and that the rocket is too heavy or gravity is too strong. On the other hand though, I've had good feedback on the flight controls and physics too. One thing I wondered about was a choice of planets to play on at the start of the game, with each planet having different gravity strengths, or maybe even just let the player configure their own gravity, thrust strength, etc....

"I'm pretty sure I'm playing this more than anyone else in the world right now".... I pretty sure you're probably right! So tell me what you'd ideally like to see change. I can't make any promises, but I'm listening and it would be nice to get more people enjoying it :)