I think a lot of newby builders misunderstand warmongers
In warlord diff (and chieftian too) , the AI players are given a pennalty to production and growth. If you build your first settler when the AI has 3 city's then ither your expansion strategy is seriously flawed, or you where given an extreemly unlucky start. (in the middle of the jungle or something)
What I usually do is settle on the spot, or move one tile (but not more than 1) and then build 3 10-shield units (usually 3 warriors) The first 2 will explore right away, the 3th stays a bit closer to the city. Then I will start on a settler.
Once that settler is build my worker is done improving about 3-4 tiles near my captal, and will start on improving 3 tiles near my 2th city.
The settler removed 2 pop so the city is likely back to size 1 again, I will then build ither my granary in the capital or just build 3-4 more warriors. And then the next settler.
My second city will build a warrior while it is growing, and then a worker. The worker will remove 1 pop from that city so I will build an other warrior again while it is growing again, till I can afford to build a settler from that city too. (or it builds a granary aswell instead of warriors)
Once the first ring of city's is build, the city's further away from the capital have some more red shields, so it can only do 1 shield per turn while size one. Combined with 2 surplus food per turn it can build a worker every ten turns.
As you can see, I will build settlers and workers at an increadible rate, becouse settlers and workers cost pop points, my city's will rarely grow above size 3 and almost never above size 4. When the expansion fase is over, I have a huge army of workers that will quickly road and improve all the land. While my city's are building markets and libraries, they grow (becouse no more pop is removed) and quickly become ver powerfull. This will result in lots of gold (from the roads) so I can create happyness with the lux slider.
After that, you can decide to build temples in some city's if that happens to be cheaper than the lux slider. A warmonger would instead conquer a lux resource.
If you have enough lux resources about, you can do without temples or cathedral's at all.
Only if you plan to do a culture victory I would suggest building your temples earlier (at the cost of building warrior in between settlers)
If you go for the space race you should build fast offensive units instead of temples and cathedrals. The best way to have peace is to prepare for war. You don't have to use the units, you only have to have them availeble.