I'm going tho leave the nose cap hole as the standard size.
The barrel isn't floated, it bears on the centre line of the forend all the way from the centre band to the tip of the forend, the idea of packing the guards is to hold the barrel down and dampen vibration, don't know the physics I've just seen it on a lot of range rifles, but as it stands I think it will be fine, we'll see. Easy enough to retro fit, but if possible I don't want to add cork, I'm pretty sure they didn't do it on the HT's, correct me if I'm wrong.

The only H bedding I'm familiar with is a 3/4 inch wide by 1 inch 'pad' under the first inch of the barrel and fully floated from there to the tip, thats what is on those pictures of an H target I posted here about 4 weeks ago.It was making cloverleafs at 25 yards.
The other H method I know of is like the No4, bedded to the mid band and floated from the band to the tip.
Both have the nose cap opened up quite a bit.

The only time I've heard of the style you've mentioned is in James Sweets 1954 book and is referring to packing the barrel channels on stock barreled no1 mk3's, which resulted in nearly 1 MOA at 100 etc, not bad for a stock barrel over iron sights, huh?

The cool thing with your approach is you can work your way through several methods and find which your rifle likes the most. I think my only suggestion would be that as you're damping the vibes the way you are would be to make sure the nose cap attaches smoothly and squarely without torquing the barrel at all, and to use paper shims to make the hole in the nose cap is a tight fit on the barrel, instead of a potential 'buzzy' fit, usually a single layer of paper at 3.5 thou for common A4 paper, is enough to make a perfect push on snug fit.
Oh, and btw something I've seen on the enfield target rifles I've had from the golden days is that the barrels lay on the wood on a layer of graphite something, like a powder, probably helps it return to center.
All the best, looking forward to seeing the perforated paper ... with one ragged hole