Putting it on PS+ would directly contradict their business strategy. Because they support the game with major free updates & expansions (and ports), they've been able to continue to sell a lot of copies over time without doing heavy discounts. I think the chance of it being a free PS+ game is basically nothing; your best bet if you want to play it is grab it in the next 25-50% off sale.
This. A lot of people seem to be wondering how they manage to spend 2 years+ producing kickstarter-promised DLC, or asking when it's going to be free because some indie games end up on Ps+. It's because they keep refreshing all versions of the game that gives it high visibility alongside good word of mouth, that it keeps selling at near enough full price when other indie titles are on sale for peanuts 18 months after launch.
Once they realised they had a hit on their hands it made sense to keep SK as visable as possible for as long possible, it's also buying them time to plan out and think about their next project (that won't have the frontloaded safety net of a massively successful kickstarter) before committing to it.
I've bought three versions now, the 3DS one as a kickstarter backer (still the only project I've backed), and then a physical copy on WiiU and a download on the Vita too. Easily my favourite new IP this gen.
I think a Switch port is all but inevitable and I'll end up buying that too, YCG have been one of the good guys recently. I think they are up to 60 updates now? That's been cool too, letting people know what's going on with it.
) is that it means their next game is a long ways off.
