The carbs themselves are not complicated. What is complicated is how to apply them to an individual runner intake on an American V8.
IF all that you had to "adjust" them for was constant WOT applications, that is simple.
Attempting to apply an analog system (carbs) to get the results of a digital EFI on a car that needs to be street driven is another story all together.
EFI essentially is tuned to every single rpm by having a ECU match a pre-determined a/f ratio/rpm. Carburetors can only be tuned to certain points of the rpm and everything in the induction system is part of that.
Weber IDA's are not unique to that. You can clearly see the methods used on Holley carbs as well although generally speaking with only a few exceptions, you don't need to deal with reversion with them.
The intake manifold originally "designed" and built for Detomaso by Ford through Hoolman-Moody is really one of the best ever produced for a V8 but that may actually be more co-incidental then intended due to the fitment of the carbs on the manifold.
The distance from the intake manifold to the edge of the throttle plate was thought to be optimum at the time and is probably as correct as you can make it to be.
With EFI, the manifold ALMOST doesn't matter as long as it doesn't restrict maximum flow to the cylinder.
Going to EFI is the only way to make it better and eliminate the "Weber exhaust cloud" and heavy idle.
There you can optimize WOT at a predetermined a/f ratio, probably 12.5:1 and idle it down to 14.6:1, run a more radical cam profile, without the engine going into a revolt.