Wonders,
there's a huge difference between Imm and Deity, and most affected imo is TGW.
While barbs are much slower to enter cultural borders on Imm (happens at ~3 cities average among all AIs),
on deity this can happen from turn ~35 on.
I will happily build TGW on deity with stone or IND (sometimes even better than stone, as no wheel & quarry needed),
if scouting reveals that AIs are far away, or larger tundra / desert areas close, stuff like that
There were probably more deity games lost to barbs than AIs.
Much more time on IMM for setting up fog busters, and barb archers that might drive them away before things are sorted also appear later.
Pyras are connected to how you estimate your happy cap, available land and commerce potential.
Example..if you see no early happy resis at all (no gold, gems, ivory, furs..), +3 from Rep can be huge.
If you have CHA, happy needs are less dire.
Good food around favors running specialists, with Rep scientists becoming as powerful as gold mines for research.
Less food and Ivory + Furs could mean that Pyras are a luxury, and you might prefer fail gold (or not bothering with them, i.e. if stone is further away).