Remaking Flyer transformers would be a waste of time and resources better devoted to S FasTrack, rolling stock and locomotive development. Particularly as Flyer now comes with either FlyerChief or Legacy.
Even if Lionel would remake, say, the 30B transformer, it would be like the modern ZW: A repro case with internal electronics powered by external bricks. Probably costing around 500 bucks.
There are plenty of alternatives for transformers out there.
Rusty