LaGuardia Community College has implemented all three typical pathways at scale. They recommend adding pathways one at a time.
The pathway to calculus is perhaps most interesting, They give students fewer credits towards graduation (reflecting not counting Intermediate?). They use OER materials. They merged elementary and arithmetic as a pre-requisite so that students can then do a complete precalculus in one semester.
It might be worth a look at the pathway to calculus if and when we are ready to do this. The AMATYC conference proceedings from 2018 will have these materials.