I definitely disagree that there's little difference between Neil solo and CH. Time on Earth is easily my favorite thing Neil's done since 1996, and it's the one record where certain songs truly seem to harken back to the band's heyday. Nobody Wants To, Don't Stop Now in particular, but others too. There's a certain magic there when those guys (or even just Neil and Nick) play together, no matter how much Neil pretends it doesn't matter what name you put on his stuff.
Interesting that we all hear the same things differently. Time on Earth was, of course, a solo album (albeit with Nick on bass) until it had been completed, at which point Neil decided to reform the band. At that point, it made no sense to have CH touring a solo album and so it was badged as the CH record it never was (by way of token gesture, they recorded four new tracks for it but even so, musically it remains a solo album). And, to me, it sounds much more like a Neil album than a CH one, in terms of songwriting and also in terms of sound.
Perhaps that's because Neil consciously tried to get away from the CH style of songwriting when he left the band the first time around (Try Whistling This being an oblique reference to that fact). As a result, very little of what he's done since sounds like CH (honourable exceptions go to songs like Anytime or Amsterdam) which is why I don't really yearn for a reunion: much as I love seeing him onstage with Nick and Mark (and, don't get me wrong: I do), it was Paul Hester who gave them their swing and made their shows so spectacular.
I've actually found their post-reformation live shows slightly awkward sometimes as Neil tries to share the banter with Nick but it often seems forced; like they're trying to keep that mad stage banter going but it was Paul who drove that stuff.
And besides, a CH reunion would just force all of those gorgeous solo songs back in their box. And, if I'm honest, I'd rather hear Into the Sunset than Into Temptation at this point in time...