If it's too big then it draws less fuel through the boosters making it leaner so that MAY help but I'm not sure on that w/out trying it and seeing for yourself. Smaller less powerful motors are usually easier to tune but many factors come into play like, weight, vert, gears, altitude fuel etc......

Actually I meant, if the carb is too big, don't progressive secondaries help smooth out the response?
Also thinking of something like a TQ with small primaries for good throttle response, but huge secondaries for wide-open. [/quote]
My dealings with carbs, both multiples and singles with progressive linkage is the right foot determine how smooth the car responds to the throttle peddle
Many carbs will bog or backfire if opened to quickly when not tuned properly, multiple carbs included.
As far as tiny primary carbs with great big secondary carbs like the Quadrajet and Thermoquad carbs can be made to run well, the fuel distribution at WOT to each cylinder is another tuning issue to deal with though also
As far as smooth operating, being a drag racer I like no bogs or back fires
Tune it until you love it

In addition to the velocity-operated (AVS, Q-J, TQ) and counter-weighted (AFB) secondary air doors, some also have a dash-pot (vacuum diaphragm with a bleed hole) which slows the linkage activation as an additional tweak against bogging. These can easily be added to existing linkage and made adjustable by using a jet as the air bleed regulator. It can be open to the air (not filtered) and easily accessible because the air doesn't enter the intake tract.
IMHO some manifolds for staggered bore carburetors (Holley 4011, QJ, TQ) were simply made by altering the flange footprint and bolt pattern of an existing square bore manifold - but no thought as to moving the carburetor forward to improve the inherent front-to-rear bias. Has anyone seen attempts to re-locate with dyno or track results? This may even be legal (or at least nearly invisible)!

Driveability is very subjective. Driveability on the street with a four speed transmission can be super touchy. I'd start with the dual AFB setup since those carbs have nice idle circuits and driveability is usually pretty nice. I've seen people asking crazy money for those rat roaster intakes so another option is to sell that stuff for a pile of cash and then go buy something that will work really well on the street. I can't tell from your questions if you are more into driveability or looks. If you just want something to look great and you don't really care how it drives then the rat roaster is a good choice. If you want to be able to drive the car smoothly at slow speeds down residential streets then you should probably pull the trigger on a different intake.

I’ll define drivability for me, no bogging, no idling at 1500 rpm, no having to keep patting the gas to keep running. I want the hammering hard hitting rapid sound FOR ABOUT TWO-THREE hours, then I’ll drive the SRT auto Challenger. LOL

If it was my car I'd probably keep the rat roaster intake and put a dual Sniper setup on there with a Hyperspark distributor. A dual throttle body EFI setup would have a fighting chance of working on that intake. I'm not going to guarantee that it will be super driveable, but it would be easy to tune.

Does sound attractive