Count me in as another fan of that new Mack concept! There's definitely room for more thrilling spinning coaster layouts - they seem quite an undeveloped ride type on the whole. However, after the airtime hill, the layout seems a bit minimalistic. It's essentially just the same element (immelman/dive loop) repeated four times, just in different directions of course? I'd much rather see a bit more variety, especially since Blue Fire's inline twist looks fantastic with the spinning car. But still, I love the the 2 in 1 idea - that'll make it seriously rerideable.
I wouldn't be objected to it, but I'd consider it highly unlikely, even beyond 2018. Remember Walibi Belgium was the one that just installed Pulsar, a similar concept and with that, also have two other shuttles in Psyke Underground and Cobra. I know a full-circuit shuttle spinning coaster is different, but it would still be the park's fourth coaster to feature a backwards element, and their third to be launched. I could see a Big Dipper fitting in better though!