If all limited access roads are made toll roads, then you can expect meatheads driving as fast as possible on the non-limited access roads to save the tolls. Personally, I don't think that is a good answer for transportation in general, and definitely not for bicyclists.
I personally don't want to see the few nice 2 lane roads congested with too many cars going too fast to save a couple of bucks each on tolls.
The whole highway system (and city/county roads in many areas) are in terrible shape because too much of the money has been spent on new roads instead of keeping the infrastructure up to par. It is easy to get a portion of the people more excited about a new highway to make their commute shorter than it is to get them committes to spending their tax dollars to fix the crumbling roads.