You do realize that the only MOBA that didn't try to shake things up was Heroes of Newerth and DotA 2?
Every other one did something new.
Not exactly true. For example, Infinite Crisis is essentially a reskin of LoL, it's practically identical (and coincidentally shutting down soon). What I meant was that they seem to be making larger changes to the formula. The differences between, for example, DotA 2 and LoL are not that great. The basic setup is quite similar, even the map is almost identical. Even HotS, which differentiates itself a little more with its various maps and larger array of objectives, still uses essentially the same exact formula as DotA, just in a more simplified form.
Forgot about Infinite Crisis. :D
LoL added bushes, removed denying, lightened death punishments, puts effort into balancing, etc etc, made the genre easier to get into and play. That's plenty new and different.
Smite added third person camera (maybe other stuff, never played it). As a change, it's not a big one, even if it does affect gameplay in a big way.
Dawngate tried to innovate with jungle changes (deprive enemies from passive money by stealing their mines, etc).
Demigod gave heroes skill trees to costumize them, more than one map, so on.
Even HotS, dropped items (big thing, even if I personally dislike it), gave towers ammo, this and that.
I won't drop LoL for other MOBAs, but I do keep track of what changes they are proposing, and all of them offer something.
I don't know what Battleborn offfers yet apart from the perspective change (trailer doesn't even make it look like a MOBA, imo), but we'll see.