After thinking a lot about it, I ended up with the solution. Here it is:
First, I started using FireRed. I started the hack repeating to me: "This hack will be fun to do, and you will have enough time to work on it and finish". But FireRed was very limited, so I changed to Emerald.
I made a lot of improvements to the game and even added some new features to it. But the problems returned. First I thought they were minor, but after getting a HUGE error with the main Tileset I realised that it was too hard for me.
Now I have a new project in my mind. The hack won't end like this, of course, but it will have a very big change. I'm not telling anything about the project, but I hope the project works as I want and I can release it to public.