It does look very nice, yeah. It'd be amazing to have Essentials working properly on both PC and Mac if we did eventually get it working, and even better to have fangames playable on portable devices (although in the case of iOS I can only imagine that'd involve fiddling around with sideloading and/or jailbreaking, since it's prooooobably a bad idea to attempt to distribute fan-made Pokémon games through Apple's App Store... granted it'd also be a bad idea to distribute through the Play Store, but at least sideloading on Android is much simpler). The .js plugins seem like they'd be pretty convenient, too, even outside the fact that I personally know more JavaScript than Ruby. Also, mouse support out of the box!
Bit unfortunate that it's $80, though. That's... actually quite cheap compared to other top-tier modern game makers/the paid versions of otherwise free game makers like Stencyl or Construct2, and so is probably perfectly acceptable for people who are serious about game dev in general, but I can see it being a stumbling block for some. You may not want to pay that much if you're only planning to make one game, for example. XP's much lower price will probably keep it pretty popular for a while yet. That's not a bad thing, mind, as it's always nice to have options.
I'm not going to lie, there's a tiny part of me that's tempted to see what I could do as far as attempting a conversion for the Essentials kit.. Of course, realistically that is a terrible idea, because at this stage I don't know Essentials or RMXP anywhere near well enough to handle all of that work properly. Wouldn't even know which scripts to start the port with, haha. I think for now I'll just content myself with messing around with XP and actually learning how to do stuff, and then, hey, maybe one day when I actually know what I'm talking about and have some time to boot, I might give it a poke. Unlikely, but it's nice to have a few pie-in-the-sky project ideas, eh?
We'll have to see what RMMV is like when it comes out, at any rate! Maybe it'll be relatively simple to convert Essentials and just require the (massive amount of) time needed to comb through every script and port it from RGSS to JS, maybe it'll be a lot more difficult due to changes in the way maps are handled or whatever else might be different, but either way it is nice to see the RPG Maker series finally catching up with the times and should be very good for original RPGs if nothing else.