I'm a little ham fisted in the dark I guess. Metol sensitivity has me wearing gloves, Even though DD-X doesn't have metol. I was a D23 guy for years.
One thing for sure, spotting and repairing scratches is sooo easy with photoshop. vs. the old way with a brush and tone'.
Used Kodak tanks to process 4x5 for many years in my early industrial photographic life and didn't find any problems with streaking etc. After that, when I went independent, it was always TXP in 120 and FP3/4 or HP3/4 in 35mm. It was also D76 1+1 for everything. As has been said, in 4x5 there isn't going to be any visible grain from anything unless you do something really dumb such as over-expose and over-develop.
By the way, pre-soaking is intended to prevent uneven development densities by making it easier for the developer to cover the entire surface quickly, also to prevent the occurrence of air bubbles. Film with built-in wetting agent? Bit of hype, I think.
Kept in well sealed dark bottles, D76 stock solution lasts for ages; Ilford's ID11 is the same poison, if Kodak drop out of the game.
Can't comment usefully on LF scanning, neither have I got the spare bread for a dedicated roll-film scanner, much as I'd like to have had some years ago when still running 120 gear.
But that's life - it moves on whether you are ready or not.
Ciao - Rob C