Don't delete the originals, though! You might lose something of merit - a nuance or quality of tone in a line that is different in a subsequent version. Little things like that are so important in radio/audio work.
Book 1 Chapter 1: A Long-Expected Party
One slip - "The eldest of this was Bilbo's favourite, was young Frodo Baggins." (The first "was" should be an "and.")
September 22nd - Saying this aloud, I would say September THE 22nd - but maybe that's just a British thing? Not sure.
10.49 ish "reported the Gaffer" should be "retorted the Gaffer."
Shortly after: My Sam says that everyone's been invited to party" (a missing "the"?) Makes it come across a little like Yorkshire dialect "to t'party." (Maybe I notice this more than most, being a Yorkshire girl myself).
AFAIK, "Nasturtiums" is generally pronounced "nasturshams," not "nasturteeyams." (Not that it's pronounced that often!)
But we had some in our garden when I was a kid, and it was "nasturshams."
"A draft (draught?) of cooks" - should sound like "draft," not "drought."
It's "elevenses," not elevensIes."
'PROvender" - I think the stress should be on the first syllable, not the second. However, the second may be North American pronunciation? In which case both are right. I would hate to point out things as mistakes when they are only different/regional varieties of correct.
Am enjoying both the narration and the voices of the rustic hobbits at the Ivy Bush. Also enjoying the party in the background, although at times it's a little too loud and nearly drowns the narration. Listening to the fireworks at the party at the moment - there was a little bit that sounded like the audience at a live football match! - just for a moment, and then the narrative says "like an army" and yes, the sounds resemble those of a battle.
It's interesting that Bilbo's party speech sounds as is if it's coming from a distance, as it would to those nearer the back in the party tent. Just for a moment I thought of BBC Saruman's voice! Bilbo's voice sounds like Frodo's, but less high. (Another place where the deep impressions made by the BBC version stick for me - but I have always imagined Bilbo with a heartier, more hobbitlike voice, a contrast with the more "elvish" Frodo, even though they are both Elf-Friends).
Rory Brandybuck's line was fun! Nice accent and delivery here.
I feel a little pause was needed before "Frodo was the only one present who had said nothing."
The earlier part of Gandalf and Bilbo's conversation in Bag End feels slightly rushed. (In fact quite a bit of this chapter feels a little rushed, I think).
Bilbo hesitating to hand over the Ring echoes Ian Holm's performance - in this case his performance of Bilbo, not Frodo! Especially "Here it is in my pocket ...." And I can see Sir Ian's eyes as he says "My Precious ..."
Gandalf: "It will be my turn to get angry soon. But if you say that again, I shall." There shouldn't be a "But."
"Mr Bilbo Baggins has gone away [AND] as far as I know, for good." The "and" isn't in the original text - but I don't know if you are strictly going for an absolutely exact reading. (It's far better to get the effect right, I think).
Bilbo singing: "The road goes ever on and on." Personally I'm not really a fan of the tunes used in the film for existing songs in the tale, especially this one. However, legions of your listeners probably love it, and their views are just as important.
Just heard Merry's voice for the first time. I personally think Merry and Pippin work better with Received Pronunciation, but I won't go on about it.
Otho and Lobelia Sackville-Baggins are quite rustic, too. I think RP is more appropriate for the middle-class and aristocratic hobbits (as Tolkien said when he was consulted regarding a very early radio dramatisation of LOTR which has not survived. I think it featured Oliver Burt as Frodo and Prunella Scales as Ioreth). However, using the same accents for Frodo, Pippin and Merry would make it much harder to tell them apart with one person providing all the verses, of course.
N.B. Please note that when I comment on voicings of different characters, that is just my own reaction. I think the variety achieved is brilliant. And my comparison of the effects with previous versions (especially the radio one) are not judgements, just observations.