Would like to throw in the Chocolate Firepot and Tuohy into the tight five reckoning. Tuohy in particular has been in great form, another guy who could claim to be the form lock in the country, and he's got more than decent handling and athleticism. Deccie Fitz has been doing well for him in that he's stayed fit and actually done things other than scrum, I appreciate that's not the greatest endorsement in the world, but he's the only Irish tighthead other than Ross who can definitely scrummage at international level. But I'm not sure either would be troubling Ross or Ryan at this stage, barring the injury talk. The other options can trouble Ryan, in that they offer different things, but I think Ryan and Tuohy are fairly similar all-rounders.
The 12 question is a bit more interesting. I haven't seen D'Arcy convert provincial to international form for a long time but we know why that might be. Luke Marshall can definitely do things at international level but he has not made the definite case for the shirt at provincial level. Its possible Ulster are currently benching the best 12 in Ireland. I think Eamonn Sheridan's inclusion in a squad is now a matter of time, he has started like a train for London Irish. However, the sensible thing for now imo is to give the shirt to Marshall and see if he can keep it - and if you're doing that, you don't rotate him. Certainly by now I fail to see what qualities D'Arcy has over him other than experience and familiarity. Not discounting those things, but I don't think that's enough for a horses for courses approach.
Jackson is in great form but is a season away from putting real pressure on Sexton imo, ditto Cronin with Best, both guys need to show consistency, Healy and Heaslip are both secure for a game you really want to win and I don't think there's any room for experimenting there this autumn.
Which leaves 6. I want to argue for Henderson but its really difficult when he's not getting the time. McLaughlin is an honest workhorse and no more, he'll do a fine job but will never be a standout. O'Mahony, eh, clear talent but not enough to be ahead, and possibly not the best balance. Wilson has played really well when at 6 this season - and I think you could even go with a Henry/O'Brien combo if you were so minded, that looks good to me. Would certainly free Heaslip up to concentrate more on his carrying. By far the most interesting selection decision in the squad if you ask me.