An interesting question. The value of the car is in the eye of the buyer. So I don’t know what people want. I have a Lotus Europa and most people ant a fast car and originality is secondary. The Tiger people seem to value originality more.
I am building a Tiger that is as close to an original Tiger that I would have bought, if I had the money, in 1966. All the original LAT options that I think are cool.
What Tiger are you building? You need to have a road map that defines what you want to build within your budget.
Fuel injection would be great, but it is not original. However, I do all the work on my car myself. Carburetors can cost a lot to get right. A fuel injection system just requires someone that knows what they are doing and a laptop computer.
You could build a restomod with disc brakes all around, a crate 500 HP engine and an overdrive 5 speed. It would be a much better car than original. Or you could buy a modern muscle car that would be much safer and faster at half the cost.
It all depends on what you want and your budget.
That’s my 2 cents.