Kind of a dumb question but how so are the mods more limited? Is it just that without it the car itself is a little more selective of what it works well with? Also if I do the MAF conversion would it eliminate that issue?
The SD and MAF are two different computer control stategies.
In the SD system the computer gets a signal from the MAP (manifold air pressure) sensor telling it what the vacuum is. The computer, through its program, then determines how much fuel to add. When you change cams and such it changes the vacuum signal so the computer ends up adding the wrong amount of fuel. It can cause really bad surging idle and other probs.
With a MAF system the MAF (mass air flow) sensor tells the computer what the mass of the incoming air charge is. This will not change with vacuum or anything else so it provides a more stable reading for the computer to do its calculations on how much fuel to add.
But the big answer is that if you do a MAF conversion you can put the mods that you want to in you list on. If you don't, well, it won't be a very fun car to drive.