To'omua & O'Connor would be the most likely to be in most ANY XV. From the Forwards you'd imagine Tupou, Slipper, LSL (Lukhan Salakaia-Loto), MAYBE Simmons, Wright & Hooper would probably be only forwards locked in for most sides.
The possible options (as I see them)
I don't think anyone would disagree significantly with writing off Tupou or LSL (Lukhan Salakaia-Loto) -- hell of a player (both of them) but just not the right personality for the job. Can't pick AAA he's under too much selection pressure, nor can you pick DHP IMO too far away and likely under selection pressure.
Wright wouldn't be an awful option -- you could argue for him being captain of a successful Super side, he makes good decisions, communicates with the officials really well, does a very good job with the media. Obviously lacking experience but also hasn't overseen the arguably the worst period in Australia Rugby history... So swings and roundabouts. haha But he's a VERY smart player, he's a student of the game even having two or three cracks at scoring a try behind the opposition's goal line (most players don't even know that's a rule let alone are quick witted enough to pounce on it, apparently too quickly).
Simmons for a year -- you'd only have to commit to him for a year he'd give you stability for this year while deciding on a direction going forwards. He's been leading the Waratahs well, he doesn't make the awful tactical decisions Hooper often does, he's the most experienced player in the squad.
Slipper is intriguing, especially if you wanted to go a different direction with someone like a Wright. He could be your 'official' captain for 40-60 with whoever you are grooming serving under him. Slipper was an institution for the Reds before his 'personal issues' (there were actually some serious personal issues to be fair). He has good leadership credentials, he's put his personal issues behind. Makes good decisions, communicates with the officials & media well and should command the respect of everyone in the room.
Hooper is obviously quite devisive, naming him would really mean you are nailing your flag to the mast, if you return to him following the Cheika era I don't think there would be anything that could justify dropping him in our near future. So I think you can only pick Hooper if you are committed to having Hooper leading your team at the next RWC minimum. Beyond that at least personally I have a lot of issues with Hoopers captaincy. He embodied everything it was to play in that Cheika era, even setting aside the actual results, that was an era that saw us regularly disrespect the officials (or at least loose the officials respect for us), it was overly combative with the media, with other coaches, with anyone who wasn't us. Hooper personally as a captain is plagued by poor tactical decisions, by awful communication with the officials. He is viewed by many as a symbol of the Sydney-Centric Rugby Australia politics. Also I suspect (or at least would argue) Hooper may likely come under selection pressure from a mixture of McReight and Wright, it'd be an awfully bad look to name your captain then dump him for a 20 year old kid.
To'omua is another interesting option, smart good decision maker, good communicator, he's got the experience. He would probably draw the most acceptance from the wider Rugby Community, as he's pretty well liked by everyone. Not too much more to add it's a fairly stock standard option. Him playing 12 would probably be a little too far removed form the ruck/scum/lineout but otherwise is a crowed pleaser.You could argue To'omua is leading the under-performing Rebels who probably on paper have one of the most talented Super Rugby squads.
O'Connor -- probably the most controversial option but I think one that has merit. O'Connor has been exceptional with the Reds his leadership both on and off the field has been a complete turn around for him. He seemingly has no ego has reflected on all the mistakes he made in the past and has grown from that. I don't know there are too many better options to have as your leader to have around your young squad, he knows because he's done it. But he's also likely well respected by the players. He's played everywhere and won big games as well as lost big games. He'd be in your XV for just about every formulation of your side. He'd not get in the way of player development. Looking at some of the articles and nightly news stories that have talked about O'Connor's work with the Reds playing in a finals -- I would imagine EVERY media outlet in the country would have a story about 'the resurrection of the prodigal son' (yes I know I'm mixing biblical stories, but it'd be that epic). Playing at flyhalf get's him a little bit closer to the scrum/ruck/lineout than say To'omua. And being a leader for a winning team should count for a lot.
I can't really see options outside those guys, and even then some of them are pretty left field. But I think those are your options.