Haha, sorry, I was 10 minutes into a game I was waiting for 2 or so years. I wanna say that the gameplay is really good, I like the controls, the only downside to it would be the stamina while running, even though it charges really fast. You can change genders whenever you want as well. I like how if you wanna fight a Micromon, you gotta look in the grass for a shaking one, rather than them appearing randomly. Same with trainers (in this case, tamers), if one of them wants to fight, they'll have a little sword over their head, and once you talk to them you get a yes/no if you wanna fight, and they'll eventually wanna rebattle later. The battle system is great, unlike pokemon where each micromon attacks per turn, it is sorta like that. If you have a micromon with really high speed, sometimes the order will go
Your Micromon > YM > OM > YM > OM > YM > YM
But I'm not sure if I'm explaining that correctly.
It also has an egg system. Sometimes, you'll come across people that will give you eggs, or some will give you diamonds, which you can use on eggs. The egg system basically works like this.
You get an egg, and you use some thing that is provided to you, and use the egg in it. You press the button, "spin" and it starts showing a bunch of different micromon. Once you put stop it will stop rotating, or going slower, and you will end up getting a rare micromon that is stronger than the ones you will find in the wild. For diamonds, you can also buy a pet, or change your avatar into another one that is not the boy or the girl, a different costume I guess. I also really like how the IAPs are not requiered, or bothersome. They don't advertise them to you. As of now, the online is very broken, as you can have level 1s and fight level 70s, but I am pretty sure they are working on fixing that.
And sorry, I've never played Monster Galaxy, so I can't answer there :/