Instead of choosing one over the other I was suggesting why not have a (potentially) balanced fusion of s/l-canceling that also adds some nice offensive options and mixups?
http://www.smashboards.com/showpost.php?p=5633295&postcount=90
Your idea of s-cancel with a tradeoff is similar to what powershield-canceling would be except:
1) The default aerial lag is reduced to half on normal landings.
2) The actual cancel itself cancels all lag similar to s-canceling.
3) Instead of it just canceling into a normal shield it cancels into a powershield, which also allows you greater offensive options in using it by allowing you to cancel directly into an A or B attack.
4) For performing the ps-cancel, however, it drains a good amount of your shield in exchange.
I don't really think of it as 'punishment' for lag-canceling, but as a tradeoff for the greatly increased offensive capability and lag reduction. The main reason I like the idea of having some kind of tradeoff is that if it's just less lag for free you might as well just go ahead and do it every single time like normal l-canceling, which offers no depth at all for the actual use of it beyond the reduction in lag itself, while the ps-cancel would add new depth and require more skill in knowing when and how to best apply it.
It also makes the defensive game not as clear cut and 1-dimensional since the attacker doesn't always have a best in all situations or fixed course of action that the defender would know they are doing and how to respond accordingly.
