Looks nice but I don't think it will fit on 35,000t SD (closer to 40 me thinks
vanguard was 45 how have you cut 10,000t ?)
I have tried loads of R class rebuild myself (as have loads of my betters) they all fall down on,
- Never acceptable (prestige, service life, performance) to use old guns/mounts till too late (emergency war class) to actually get them finished.
- Prestige, RN goes first class, BB are the most important ship (and only just finished limited in numbers by treaty) so unacceptable to build 2nd class battleships (who will only be 1/4 cheaper and will slow down real BB production/ eat up numbers in any treaty)
- Service life, they are going to serve for 20+ years and rule the waves (what are you talking about CV are just the eyes of the fleet the real fighting is done by battleship !)
- Performance, you are really going to saddle the RN with lesser guns than Italy, Germany, France and Japan ! (and USA)
- The old belt is too week (thin, short and old quality) so you need new that cuts into other new BB production. (and you will need new deck cutting BB and CV)
- can't get 4 x 2 15' on a 35kt ships with desired speed (28Kn) and protection (ie as KVG), going to 3 x 3 (or 2 x4) works but doesn't save much as the mounts cost a lot, you might as well have new guns as well.
Apart from that with hindsight that you only need them for 8 years (37-45) they will become CV escorts by 43/44 that numbers matter (no treaty) and you only have 2 years (37-39) to build them they make very good sense.
Back to your drawing I like, maybe to much AA for 39 ? (don't like turret 2pdr due to reloading and deflecting shells down, 4 or 6 should be fine on superstructure) (and don't think your numbers add up ? 5 x 8 not 7 x 8 ?)