I would love to see this experimental plugin becoming an native plugin, because it's pretty much essential. Having to buy expensive third party plugins that uses old nw.js and old Steam SDK versions is kind of disappointing. Please, don't make us wait for Construct 3 to have this feature implemented natively, we know that Construct 3 is not coming that soon.
The Steam4C2 plugin is always compatable with the latest stable version of NW that has proven to work well with steam. So saying that it needs old nw.js versions is wrong. A new nw is on the way that will solve many problems that we have had earlier and you'll see that Steam4c2 will be updated to work with that one as well. And the steam sdk will be updated if there is any important changes added which almost never happens so it really doesn't matter at all.
So if you have a game ready for steam then just pay for the plugin and you'll have steam achievements and stats in no time. You'll have the money back in sales the first day of release anyway.
Best of luck with your project