I'm glad that the allies system is bringing you one step closer to the green side Trokair.
So my first question back is what are these going to be potential allies to, which does affect what options are the best for you to go with. Even though that is the case, I'll gladly give some honest Orky opinions on your post.
Firstly every Ork unit really need a Bosspole. Let me reiterate as it is truthfully the most important thing for Orks, they NEED a Bosspole, especially when operating in units under 20. Without one, they will retreat from the field before they can truly maximize their full potential, and when such an important piece of kit costs so little, there is very rarely a time that you can't find a way to fit it in.
Warboss isn't bad, however in 6th I would typically recommend a Big Choppa for a Warboss over the Pk. Yes you loose some strength, but by picking the Big Choppa you can utilize the Warboss's Initiative value, which is the highest among Da Greenskins. I personally am not an advocate for Kombi skorchas, but I typically am not a fan of any Kombi/Combi weapon in the game itself.
Option 1, the Nobz.
A lot of Ork players that use Nobz are big on Cybork Bodies. From a modeling aspect it's fun, and Cyborks always look dynamic on the table, and from a gaming perspective that Invul save is going to be used a lot more than you think, particularly when the Armor Save in question can and often will be negated by enemy AP. I'm not saying ditch the Armor, but I am saying to consider the extra points for Cyborking. Grot Orderlies are also really nice, and generally I'd take a couple over the Kombi-Skorcha Nobz, but as I said before I'm not really a fan of Kombi.
With Option 1 (and the Boss attached) Challenges will be an issue. For some reason Nobz in the squad do not have the Character rule, but the Painboy will, meaning you will have to choose between your Boss or the Painboy when Challenged (or issuing them if you'd want to do that I suppose). It's a tough one because you never want to loose an HQ option, but my advice is to try your best to keep the Painboy alive, he really helps keep that highly expensive unit operating.
Lastly with Option 1 I have to bring up the Footslogging nature. While I mostly play Footslogging Orks these days, I don't bring Nob Squads because they cost a lot of points, become giant bulletmagnets with less survivability than expected, and frequently I've found that many player overestimate their killing potential. Now were a slightly smaller unit of Nobz mounted on Warbikes, I'd be singing a different tune.
The Bikes are speedy, have the Exhaust Save (which personally I think was the origin of Jink), twinlinked goodness, and of course that Toughness Bonus. When the current codex was released people everywhere were complaining with screams of "overpowered" and while many still consider Nob Bikers an overpowered Deathstar, I think that there effectiveness is really dependent on keeping the numbers between 5-7, utilizing your movement, and remembering that has bulletmagnets they will be supporting the rest of your force by being something that your opponent will focus on.
Option 2, The Trukkboyz
While I am a fan of Eavy Armor on Nobz leading Boyz squads (even moreso in 6th Edition), I don't advice units of Ardboyz. Yes I'm personally not over the injustice of making them a 0-1 choice, but more than that they are overcosted, particularly when much of the weapons in the game have an AP that will bypass that armor.
An old adage of the army that as proven true multiple times over is "The best Upgrade for Orks is More Orkz", and frankly I feel that very true of Trukkboyz. Unlike the larger squads of Boyz, these small squads are going to get killed. It's not even in the realm of possibility in my mind that a single unit of Trukkboyz will survive. Two units maybe, but even with just one you have to consider it already a casualty, that if your lucky will draw a decent amount of fire away from your army's core and cause some CC disasters for an enemy unit that would rather be shooting.
I personally would never put a Warboss in a Trukk, in my personal experience it's a poor choice and a waste. But that has just been my experience, yours may very well differ, and I know for a fact that Skeetergod will likely sing the praises of Trukkboyz when he sees your post.
Further ideas...
I really hope that I haven't given you the wrong idea, Orkz are an excellent add-on to an existing army, it's all a matter of knowing what you need and the Orks can provide it. In truth I think they can generally provide a lot more than most armies, as I have found the Orks to have such a wide variety of possible builds, which in itself makes them great Allies for just about any force. (No wonder Ork BloodAxe Mercenaries have survived in the Fluff all these years!)
Like I said in the beginning, knowing what your going to Ally these Orks with can actually be important and influential as to which choices to make. For example if you need an ally that can fast respond to issues, or can just keep up, there is the option to take Wazzdakka (who moves Bikers to Troop Choices) backed by 2 Biker units, and possibly a group of Warbuggies or Koptas for some additional fast Anti-Tank.
Or if you know your own Troop choices are going to mostly be dedicated to attacking the enemy, but not great at holding Objectives you could grab Mad Dok Grotsnik allowing you to Cybork every Ork choice, and get a bunch of Cybergrots to hunkerdown on an objective. Or if you know your opponents have difficulty knocking out 2+saves you can grab a Warboss + 1 unit of Troop Meganobz and a unit of Elite Meganobz.
You can even grab a Big Mek to provide a KFF over a couple large mobz to screen the rest of your forces, or even take the Big Mek to get an extra Orky Dreadnought. Like I said, there's lots of Options that the Orks can bring to the table as allies, its just best to know exactly what you need/want.
Peace
~OD