Hi spaventapasseri,
Where will the basketball go, in the image? Between the horns? Or maybe behind the bull....so that it looks like the team's logo has been stamped on the ball itself?
When you say "....a realistic ball...." do you mean like in photorealism? I'm not sure how it would look to have a realistic basketball, together with the logo's bull, which is something like a cartoon style. It might bring a kind of conflict to the drawing as a whole. Although....if you did make a large basketball behind, and the logo much smaller, to look like the logo is stamped on the ball, it would eliminate the conflict, because the logo would have to be reduced to a solid black fill. That might actually look pretty cool. But it certainly would be tricky to get the logo in that sort of radial perspective, to look like it's wrapped around the ball.
Well, of course the ball would be a circle, and you'd use clipping and blur to apply highlighting and shading. And maybe some radial gradient. There are a few different tutorials for drawing a sphere/orb/ball with Inkscape....but I think they're all for are for a shiny ball, like a marble. And I guess you can find the pattern for the black stripe on thet internet somewhere (if you don't have an actual ball). And there's a bumpy pattern on a b-ball too, isn't there? That could be done with a filter, if you wanted that much realism.
The hard part will be getting it to appear as if the bumpiness and black stripe, and logo, to look like it's wrapped around the ball. And Inkscape doesn't have any such tool.....that I know of. Although I've never used that Rubber Stretch extension. It might be worth experimenting with, for sure. You could get part of the way using Envelope LPE, but that's not ideal either. Or if you made the image fairly small, you could avoid having to deal with that sort of radial perspective.
Other than those things, I'm not sure what to suggest. But I look forward to seeing how it progresses! Keep us updated?