There are three questions here, which really should have been asked separately, but...
1.) The [optional] indefinite article before Jimi Hendrix is simply a stylistic device. In this context, it tends to "elevate" Hendrix's status as an archetype (the man appears in many guises; on this occasion he happens to be "shirtless"). See this related ELU question on the usage.
Note that OP's specific context is highly stylised/literary. In more normal contexts (e.g. - "There's a Mr Smith on the phone"), using the article is either neutral or somewhat dismissive (the speaker doesn't personally know this Mr Smith - he's just one of many Mr Smiths, and the speaker doesn't care which).
2.) I don't understand what "better" means as regards an alternative to 'singing passionately'. If OP intends the exact meaning of those words, they're fine. If he means something different, we don't know what he has in mind, so it's unanswerable (and would probably be Off Topic "writing advice" anyway).
3.) The [optional] definite article before words like television, radio is vaguely related to #1. The modern tendency is not to include an article before television, but it's still normally used before radio. I can't really explain why we tend to see something on television, but hear it on the radio. Any credible explanation for one tends to be contradicted by the other. All I can say is on television is an emerging idiomatic usage.
4.) (If my numbers don't correspond with OP's it's because there are just too many questions to track! :)
If something appears in TV/radio news bulletins we tend to only say it's on the news while it's being broadcast (i.e. - while the news is on).
If something is reported in the newspapers, news magazines, etc., but doesn't actually feature in TV/radio newcasts for whatever reason, by the same logic, it's in the news.
If something was on the news yesterday, but not today, you might say it's in the news - especially if you think it's likely to be the focus of more coverage in the coming days. In general, things are in the news for longer than they're on the news, but the preposition is primarily dictated by the technology and timing of the news bulletins.
Also note that you can be in the news just by being featured in a weekly celebrity gossip magazine, without ever being covered by TV/radio newscasts, or serious newspapers.