Peak/Prime (they're pretty much the same thing, aren't they?)
Well you've already conveniently ignored Orr's 8 straight Norris Trophies since Gretzky isn't eligible, so I'll give you that and say that Orr's two Art Ross Trophies as a defenseman (totally without peer) and this two Hart Trophies (something exceptionally rare among defensemen) may even exceed what Gretzky did. After all, Orr won one award (Art Ross) that virtually disqualifies defenders - TWICE (and it's an award that doesn't go by subjective votes). He also won an MVP award that has historically all but ignored defenders. By the way, if you want asterix, then put it beside Gretzky's Hart over the likes Hawerchuk, Liut, Peeters and some other players (unless the MVP is not for the Most Valuable to his team. It should be Most Outstanding Player, then Gretzky would likely have just as many yet Orr would likely have more).
Winner: Orr
Playoffs
Again, revisionist history with your "Gretzky should have had 5 Conn Smythes". He didn't though. Both players had two Conn Smythes, although the Oilers were a superior team to the Bruins of the 70's.
I'll give Gretzky a narrow edge there.
International
Orr is 1 for 1 for tournament MVP awards internationally. However, Gretzky was also dominant. Yet, you are right, Orr didn't have any opportunities, really. If we aren't counting Norris Trophies, then perhaps we shouldn't count International play for the same reason - lack of opportunity.
Category disqualification.
Career
A default win by Gretzky.
Complete Game
Sorry, but that also needs to be a category. If not, tell that to all those who use that argument later in the voting.
Orr.
So I have it 2 wins each. This is consistent with my stance that there is very little separating these two players.
Peak and prime aren't the same. Peak is a player at his very best - prime is the totality of the player's career before there's a decline (or after he takes a year or more to get acclimated to league and reach a strong level).
Lemieux's prime for example - i'd argue didn't start until his 3rd or 4th season, and likely ends in 97, or possibly 2001. Gretzky and Orr (and Crosby when he comes up - Bourque too) are a bit particular in that they were so consistent in their prime you can almost make the claim you're asking about in equating their prime and peak. But I still think we should differentiate.
Gretzky's peak - his best 1, or 3 seasons, or however many you feel are close enough together to be grouped as his very best. The level of peak is important, but length too. This isn't exact science, but if I had to make a quick guess i'd say:
Orr's peak 1969-1970 to 1974-75 (6 seasons) and Gretzky's peak from 1980-81 to 1987-88 (8 seasons).
Prime Orr is 1967-68 to 1974-75 (8 seasons) and Gretzky prime is 1979-80 to 1993-94 (15 seasons).
Peak:
I'd love for more people to compare the two in-depth. I think for peak Orr absolutely has a case at #1 - although at first glance I still favor Gretzky (I value offense very highly myself). I understand that Defenders win Harts less - but it's also hard to deny the fact that Gretzky won the hart 7 years in a row here. Also 8 seasons to 6 - and technically we could probably extent Gretzky's peak by a year or three if we wanted to.
Prime:
15 seasons to 8. Their peaks are close maybe - but Gretzky did it for much longer. We have to be fair and i don't see anyway to give this to Orr. 8 seasons of Orr is not better than 15 of Gretzky - he's not twice as good/valuable. Gretzky was also more consistent - even in his 8 seasons, although he won the Norris each time, Orr contributed offensively "greatly" in only 6 of those. Gretzky was a machine of offensive consistency - and he MADE his teammates better. He elevated so many people on the Oilers - moreso than Orr (who helped Esposito greatly - but this was a 2 way street imo).
Career:
As you say - a default win by Gretzky. Orr unfortunately has nothing outside of his prime - and Gretzky gets bonus points for everything he did outside of his prime.
Playoffs:
It's not about revisionist history when I say Gretzky should have won 5 smythes. He has 5 all-time great playoff runs (at least) in Edmonton - smythe or no smythe. I'm not saying he was robbed and should have more smythes and so we should count them - i am simply matching up runs between Gretzky to Orr. If you match up best to best - Gretzky ends up easily ahead. As "great" runs Gretzky has 83, 84, 85, 87. 88, 93. That's 6. He then also has many very strong ones to complement those 6. Again by sheer volume alone Gretzky easily bests Orr here. I also think Gretzky's very best runs are better than Orr's best runs (smythe vs smythe) - so it's not like Orr takes him over in quality. Even if you think he did though - sheer volume alone easily puts Gretzky at #1.
International Play:
Gretzky wins here. I'm firmly in the camp that you can't penalize a player for more opportunity. Example - when we compare Gretzky to Lemieux playoffs - you can't just pick the best 5-6 playoffs and argue "well Lemieux didn't make the playoffs in the 80s so let's not count 6 of Gretzky's runs either". Gretzky had more opportunities is a net positive for him and too bad for Lemieux. Same for Orr in international play (and this likely comes up a lot with players of past eras too with less international competition). It's not like International play has to be a hugely important component - but Gretzky is arguably the best international performer of all time, and it should count. Orr did good - but doesn't stack up to Gretzky's resume.
Norris's. I did not "discount" Norris for what it's worth. In my first post (and I get now i didn't actually write this - i just counted it in my head) I was thinking Gretzky has 2 big regular season trophies to go after (Ross + Hart) and Orr did too (Norris + Hart). So I was equating Gretzky's Ross to Orr's Norrises. Not an exact science - but just a way to quickly compare regular season accolades (and yes Orr's 2 Ross are extremely special and he can get bonus points for those). So no we're not disqualifying Norris trophies nor International play nor anything else, nor should we.
Complete Game:
I'm not saying complete game isn't very important - i just don't view it as a category of its own - but rather a component of each of the above categories. ie - counter my argument about me saying Gretzky > Orr for peak by showing that no - Orr > Gretzky for peak because Orr's complete game was enough to overcome the gap in peaks (6 to 8 seasons, offensive gap, and everything else included). Same idea for prime and anything else.
It's just like i'm not considering goal-scoring, or playmaking, or other elements as categories, but rather as components of the above categories (playoffs, peak, prime, career, international).
Now if you want to break up each category above (peak/prime/career/international/playoffs) into sub categories of goal scoring, complete game, playmaking, defense, etc - that's fine we can do that. I was lumping it all at once, just to do a quick calculation.
Finally Count:
Gretzky gets the edge in Playoffs, International, Career and prime.
Peak - open (i personally say Gretzky - but this one is closer).
Not all 5 categories are worth the same. So you might say peak is most important to you and give it 50% importance in your overall assessment of final ranking - but still considering Gretzky is ahead in the other 4 categories, and at the very least should be quite close in peak - I have trouble finding a way to not have him comfortably at #1 - at least when compared to Orr.