Difficulty level isn't the main issue.
The same principles apply to every difficulty level. You have to balance priorities, to gain as much as you can as quickly as you can by identifying priorities correctly, and putting all the effort you can get away with into the things with the highest short term payoffs. Especially early on.
Lower difficulty level does not preclude smarter play. It means the AI opponents are slower, less threatening.
If you are getting lambasted on Monarch, then you are not being as efficient as the Monarch AI's at expansion and defense.
There is only ever going to be one TDG from me, and it's on and running right now. Some things are judgement calls, when there are six "good" options available, they can all be made to work. There are also "bad" options, things that waste time or are given more priority than they deserve at the time.
I suggest that you don't need a Monarch TDG at all. You just need to pay attention to the TDG's already running.
You are welcome to shadow in my game. If you post a result, I will critique it. Just that there are only so many slots available for those who get to have a result count toward the official "scored" version of the SG.
- Sirian