I have a rather complex application that is a mix of C++, ObjC and Swift. I humbly consider myself an expert in all three languages and worked on AppKit while employed at Apple. Perhaps Swift is slightly more accessible when you begin development. If you aren't familiar with ObjC syntax, Swift my look more familiar at first, but syntax quickly becomes familiar.

When you mention more sophisticated solutions using Swift, I am not sure what capabilities Obj-C lacks that would hamper it. Are you referring to the functional parts of the Swift language? Combine?