I recently picked up the 1st Ed Adeptucs Titanicus rules on Ebay and plato play in the local store. I have a half dozen if the original plastic titans plus a bunch of Eldar Phantoms.

The problems with GW bringing back Epic are cost and abstraction. The original rules were meant for a handful of Titans per side and were very detailed but playable at that size. Epic Space marine kept the detail but addedd a lot more models making games 3+ hours long. Epic 2nd ed. and later streamlined the mechanics but that reduced titans to just another model with little variation in effect. Cost is another factor because they could not print a game with SIX Warlord Titans for only $100 given the current model is about $40 for one.