I apologize for not uploading this yesterday so here you go.
The reason is pretty simple why I ship Rarity with Silverbelle and not Good Fortune. Fortune likes Rarity because she is basically his first friend, so Fortune obtained many feelings towards Rarity but…Rarity can't bring herself to love love Fortune especially to the point of if their friendship dies down, she won't know how to deal with his emotions at that point. Plus many other reasons, one of them I want to say is Fortune doesn't have any benefits with Rarity's business. His talent only involves survival of fittest, luck if you will, yeah he has money but it's limited, he left Canterlot and went into hiding…he became a background character you would say…non seeable to the naked eye.
Silverbelle however is a different story, him and Rarity not just have feelings toward each other but can easily help each other out with wealth. Both share business, Rarity with clothing designs, etc, Silverbelle with not just creating bells but with many items involving silver, crafting and selling bells is just his main item. I can easily go on with many other reasons for example, both can easy get donators thanks to their proper and elegant manners from banquets and other form of parties and gatherings, yes it might be weird for Sweetie belle that her older sister is dating a stallion named Silverbelle even though his name is one word and her's is two, but that's the only down side to this relationship that I can think of. Lastly, both can easily look out for each other and or themselves, they have a pretty high trust bond if you ask me, Fortune is uncertain, unpredictable in a way, and so forth, it's fun at the beginning but what about after? It wouldn't last.
MlpFim/Rarity © Hasbro and Fausticorn
Silverbelle/AfterVerse/Art © (me)