After years of operating experience, most manufacturers have abandoned skip firing. While it does hold for some promise, it comes with so many problems that other paths lead more directly to improvements. In short, skip fire sounds good, but doesn't work out well. A similar situation killed the Wankel engine. It too was fascinating, but impractical. Any development you can come up with to improve it (advanced rings, seals, and surface treatments) could also be applied to a reciprocating engine so that the Wankel could never pull out ahead as a better way. Much larger heat transfer area (think losses and huge radiator) and swept area (think lubrication and sluffing off residual every rotation resulting in higher emissions and huge catalytic converters) can't be fixed and buried the Wankel engine. Skip fire is a similar path to nowhere.