Any system is tricky, carb or EFI. You can spend a lot of time tuning and chasing your tail with both, but in the end, once both are tuned right, you likely won't touch either after they are set. So the main question is how you want to spend your time tuning? I have a Megasquirt system on my 5.7 Hemi swap in my 67 and feel like I have redone the tune from scratch three times now, but that's also just because I have the ability to mess with it and I'm trying new things and attempting to get the car to feel as close as I can to a modern factory ECU. I'm fighting all the little inconsistencies now like the AFR over-correcting going to work in the morning, but under-correcting on the way home. It makes near zero difference to how it feels to drive it, but by being able to record and view the data, I know something is off. I think some of it too is that I just want to keep tinkering with it, and it's as easy as changing some numbers on a program. One of these days though (hopefully), I'll get everything set up right and will never have to touch it again unless I actually change engine parts.
You could do the exact same thing with a carb though. You could chase things all day and try different rod/jet/valve/etc. combos until you get everything just the way you want it, then you'll never have to touch it again. The only difference is you had to mechanically change those things compared to changing the values in a tuning program. I think it's fun to play with my EFI system and try all the different things it can do (like traction control, idle control, fans, A/C, etc.) and gradually add features to the car, but that's also just because it's the kind of thing I enjoy doing. I'm constantly changing my car to make it as comfortable and tailored for me as I can get it because I'm the only one who drives it, so why not? It sounds like you've already got that with your car, so unless you just like tinkering and learning new things, it probably makes sense to leave it.
