Mind Control Tech. It doesn't really a problem for ladder but a problem for arena and arena has standard cards only. I think it needs to be hof'ed.
and I don't agree with Preparation because almost all of the rogue spells are balanced around this card and if you hof it, those cards will be meaningless and you need to decrease their costs. So it seems not possible to hof Preparation . Maybe after this rotation if they start to create cards as not considering Preparation.
I think the reasons you stated are exactly why Preparation would be rotated. It's the most limiting card in the game in terms of design space (you can never print a great Rogue spell that costs more than 3, because it can be cheated out). Limiting one half of a class's entire kit is really bad. I'd expect it to get nerfed before rotated, but if they rotate then we can only hope that they'll at least adjust Rogue's basic cards to compensate.
But something needs to happen. A class shouldn't be designed around a single card for its entire life.