We live in the time of engines. You can almost always do something better than big money. Most of the traditional rushes (i.e. Gardens and Silk Road) are quite often obsolete as well.
Junking is still strong, quite often, though trashing options keep getting better and better. See: Donate.
Two-card combos don't matter as much, since they come up less frequently.
Probably the biggest check on engines is availability of extra gains or +buy. If a kingdom lacks both of those things, then maybe something simpler than an engine can win.
Landmarks are huge. Make sure to read them, it's very often worth going out of your way to collect those points, even if it means executing your strategy in a manner that would be supoptimal otherwise.
Watch out for Sauna/Avanto! It doesn't seem like a powerhouse, but dear lord is it strong.
Scout became too powerful when combined with later sets, so Donald X removed it. (Joking! But seriously, Scout was erased from existence.)