lv. x cards can use the attacks and effects of the cards under them which i think makes them really cool, it does suck though that it is like a fourth evo.
but as far as "cookie cutter" decks go, that's why ultimately i like playing unlimited cause you can create decks with strategies that would never have been played by anyone using only modified cards. (plus, don't tell me that everyone wasn't using haymaker decks way back in the day and then sneasel and clefairy decks, so there will always be many ppl with the same kind of deck)
but all in all i think i like the lv x cards better but that may be just cause i've never really used any ex cards that i particularly liked all that much.