The single biggest element to expanding MTTs is late registration imo. I know that it's not entirely SWC's fault, but it boggles me that there's major poker software that doesn't have a feature that has been possible on every poker site I've ever played for over a decade.
Never liked late registration. Always just viewed it as a way to get rid of overlays, and don't see how it advantages players in the least. I suppose if there's no overlay, someone who doesn't care enough to show up on time might be slightly more likely to be dead money, but that seems a marginal benefit at best. Even without an overlay, I'd rather have certainty as to what size the prize pool is, etc., right when it starts.