Better suited for uncommon rarity...

I guess you already know it, but no matter what restriction would WotC ever print double strike and lifelink on the same card at common.

I don't see why something like that couldn't happen on the very next set or so. For example, while not particularly related, WotC has printed a 8/8 with annihilator 2 and just recently, a 9/9 at common.

The actual issue that I see with this card is that, given all the other distinguished cards, you could easily read this as 'as long as ~ legendary' since that's how they work. So it's inconsistent with that and for that reason I might word it differently so players won't 'skimp through' that 'as long as blaa' text without reading it properly.

You could just say "distinguished -- double strike". Then it's a common version of Marisi's Twinclaws. Very strong.

Indeed it would, but then I wouldn't place it at this rarity. I've noted that in limited, that "3 or more legendary permanents" isn't the easiest of things to achieve.

Normally it's not, but in this set it's pretty much "Play 3 different creatures" - which is oddly easier in limited than constructed :)

It's a very strong card once activated; the activation hoop is a more fiddly version of the normal one though - so this does really belong at a higher rarity, or in the follow-up set (which usually gets used to stretch a mechanic).

That's only if you manage to get the deck going when picking cards. For example, with my deck, I realized that I couldn't get enough distinguished creatures, so I dropped a copy of Maiden of the Day-Star and didn't ever get to play Rise to Occasion from my graveyard.

So getting a bunch of legendary creatures isn't as easy as one might think. In red, the common distinguished creatures have the following mana costs , , and . For white, those costs are and (this card). In red and white, the ratio of distinguished common creatures to non-distinguished common creatures is 1 to 2 (5 to 10), so 50 %.