Not sure about the last sentence but all the others are very good calls .
I also had a list which included Adam Reach but didn't post it for fear of getting too many likes .
If we did go up, the first ports of call are obviously the best players from the teams that didn't get promoted or from those that got relegated. Good players in their early to mid 20's, looking for the next step up or not wishing to take a step down. Harry Maguire types from 2 years ago. You'd be in the likes of Bowen's ear right after the final whistle of our game with Hull. "Always rated you Jarred......"
I think that if we went up, we'd also have to be a lot more flexible & agile with tactics. Being able to switch between 3-5-2 or 4-3-3 or 4-5-1 or 3-5-1-1 or 3-4-2-1, depending on who & where we were playing. We'd need to improve our goal threat, and whilst I'd keep BS, EM and GM (cough, spit, choke, feels dirty), I'd still like to see Tammy A & Gayle added to the mix.
I think that we'd need to switch to a flatter midfield; that's where we'd get overrun. We could put in a drinkwater to put out fires and do without the duffy/dowell role altogether and ask more of the front one/two. That's where a Gayle would be useful, always on the move. Also that's why you'd keep GM, to play as a lone striker when the need arose.
My comment about a cahill or a milner, is that i think we'd need some real experience and battle hardened players down the spine at CB & CM. If we went up we'd need a couple of players with a high degree of top flight experience, organisational skills and a callous nastiness to break up play on or near the 1/2 way line, and stop teams breaking on us. I also think that we've historically done quite well from the Saunders, McGrath's, McCall's and Cowans' of the game, who fulfille dsimialr roles (I admit Rush, Thompson & Withe were shit, but I'll gloss over that).
We'd also need to maximise our return from dead ball situations more than we currently do.