Well done bunnies
And well done Graciee
I don't think I would change the type of pellets, but then I'm very cynical and think most of the special age type pellets are just a way of them making extra money. Otherwise why do they need to be more expensive.
Shortly after Froe arrived here I started to hand feed pellets. Main reason is that Tui eats so much faster than Froe. Also I feel better if I know how much each bunny eats. So I feed SS pellets, 3 eggcupfuls between two in the summer and 4 eggcupfuls between two in the winter. The difference in seasons will obviously not be an issue for you. I reckon Tui has about twice as many as Froe, perhaps a bit more. So that probably means Froe gets about 1-1 1/2 eggcupfuls per day. I feed these in 3 sittings spread out during the day. You may not even need to reduce the number of pellets you normally feed, just make sure that Eddy doesn't pinch half of Boo's.
When Tan was getting elderly and losing a bit of weight, I used to give her extra food on the side. I used Fibafirst sticks for that, but I could just as easily just fed more of their usual pellets.
Maybe consider giving Boo a small piece of carrot now and again rather than fruit.