As a player I think that mid-season rotation to HGSS-on is the best possible solution. As a poke-dad who has to have cards for multiple decks I wouldn't mind a rotation. However I don't think that it's going to happen.
The powers that be work by a businesses model that's only partly based on copetitive play and even less so on what Japan does.
In all honesty I wish that we did things EXACTLY like Japan does as far as the way sets are released, packaging and all. Their starter decks, with shiny level X, Primes, etc. are far better than our Tins & starter decks. Their packs are better. Their card stock is better. In nealry every way Japan's product is superior to what we get.
I would be more than willing to try events done the Japanese way too. 30 card decks? Fine by me. Rotation event where you stand in line to play? Sure.
Do I ever think any of this will happen? Nope.