There are two elements to Lags and leads that I believe are greatly needed in Smartsheet Projects:
1 - Being able to use elapsed time in Predecessors i.e. +e6h for Paint drying time or +e5d for waiting for approval from external agency etc.
2 - The ability to use percentage % in Leads so that the overlap is based on the duration of the preceding task regardless whether it extends or reduces in time. i.e. -50% of a 5 day Predecessor is 2.5d, however if it extends to a 6 day task it is 3 days. Currently you would need to edit yur predesessor to ensure its accuracy, where as if it allowed % it would recalculate.
Both of these better allows the accurate creation of a Plan/Model/Recipe for the sucessful outcome desired
