Much worse than Gridlock. Being able to tap lands doesn't make it much more powerful at this cost, and doesn't make it any more interesting.

I'd like to point out, that Gridlock was spoiled a long time after I created this card.

I know.

drop it down to X1U?

Sounds fine.

(For what it's worth, note that apparently many players get confused by in the cost of common cards. Wizards still do it from time to time - Heat Ray, Death Wind, Untamed Might - so it's not something to completely avoid, but note that Wizards aim to minimise it.)

From the sounds of it, I assume cards with (X) are redflagged, but around 1/5 of the common cards can be redflagged that so it isn't really that "dangerous."

For more about NWO see: Primer: NWO + Redflagging

I don't really have to give that much consideration to NWO, since a new player isn't going to be drafting this set (if anyone does at all...well, that'd be a honor in of itself.) But I don't think this is to complicated.