I would open SR/Silver and buy two more SRs in the second reshuffle. MAYBE buy nobles if I happen to hit 6. SRs are probably going to be worth 4 VP, maybe even 5 (buying 11 green cards its a must in this setting, and 15 is not impossible if strategies diverge), so winning the split is important. After that, you don't really need GHs that much, buying estates is not much worse, because this is going to be a slog anyway. Gardens are probably going to end up between 2 and 3, without +Buy I don't see they can get to 4 VP each. Still, after SRs are out, I would maybe pickup Silvers on $3, but otherwise take Gardens and Estates and Coppers if I have less than $2. When the 3-pile is near, adapt to the point difference and beware of 3-pile version of PPR and especially, to the point-jump thresholds of SR and maybe Gardens. Not too fun to play, but perfect for simulation.
Caveat: This is missing Tunnels. Having a $3 2VP card changes the mid-game greatly. I think with Tunnles I would probably completely skip Great Halls.
EDIT: Harem is better than Nobles here, because the money density is likely to be less than 0.66 after the 2nd reshuffle for most of the game, so +$2 is better than +3 cards (and +2 actions is of course worthelss).
Also, I want a Crossroads!!!