I like it but dont love it

I cant seem to get all 5 black coins on world one #3 its impossible and I dont have the other worlds because I dont want to spend my money on only six worlds, but overall I really love this game and I love the toads although I dont like how you have to buy the other worlds to get the purple and yellow toads I think it should be the higher levels you get the different color toads you get and there should be different colored toads
But I really like this game but it would be more fun if I actually had the other worlds I think it should be that if you get all the colored coins on the whole world one you get world two and so on and then you can have special worlds and those can cost money ? for the people that have loved the game so much from there that they will want to buy it

Taylorsings20 about SUPER MARIO RUN, v2.1.1