That's one powerful blocker.

Too powerful?

At common this seems like it would end the attempts of any aggressive decks. As of yet, there is not a single indestructible creature at common. Even at uncommon the indestructible creatures have been rather overcosted (Darksteel Myr, Darksteel Sentinel). This does have defender which is good, but it still seems much like a Fog Bank which is likely just too much bear at common rarity.

Does this seem reasonable? Would 0/6 or 0/8 make more sense?

Yup.

The most similar common cards I can find are Wall of Tanglecord, Consulate Skygate, and Drift of Phantasms.

This is kinda big, but it seems fine to me.

­Wall of Ice. But while Wall of Ice didn't have reach, and was an uncommon, I think creature creep can handle this.

Except doesn't creature creep want to be pushing towards more aggressive creatures? This is the opposite

@jmgariepy: IMO a card like Wall of Ice is just too old to be of any relevance other than a (random) throwback.

@dude1818: WotC is (somewhat?) pushing for games to end within a certain turn time, but creature creep is still creature creep. I mean, Wall of Denial, Perimeter Captain and Wall of Frost are all really good blockers that seem unlikely that they could have been printed during the time of Gray Ogres other than by accident. Also, I would say that Wall of Tanglecord is arguably better than this card currently.

Also, it's worth remembering that Wall of Tanglecord was in a format with infect. Reach cards with toughness above 4 are rare already (mostly because higher toughness hold little relevance in limited where a flier with power higher than three is a rarity), so 7 feels way over the top, even on a wall. Especially on a wall, given how cheaper they are.