1 & 3 I would use on rather than by as they're not really a form of transportation to me, but younger speakers and people who actually use them may disagree. The same is true for 5, though circus clowns may disagree with me.
7 I would use by raft if that was the means of transport. If it were the result of, for example, a shipwreck, then I would use on.
The others seem fine, though I am not sure why the verb keeps changing- what's the difference between went & got to you?