I must disagree that the idea groups should all be balanced around WC or near-WC blobfests. As when you tone the scale to just a continent or less, focusing on only the conquest related idea groups is not that much better, even if that just means mixing only one of the "conquest" groups with an economic or unique one. It can lead the same result. You need a large amount of provinces to make up for the massive economic potential of trade group especially. You're just not making as much money while conquering lands you could conquer as easy anyways with that money. There's an opportunity cost there. Take one conquest focused group, and you can probably thrive in that sweet middle ground between tall and disgustingly wide.
Regarding the money versus monarch points debate, the MP-side is overrating the value of monarch points in a non-WC playthrough. You'd be right that a distant ROTW nation needs that extra monarch points, but Europe, India or China only has problems with a few of the institutions. Efficient usage of monarch power can circumnavigate these with ease. It is actually the institution embracement cost that is the largest problem for me. And it's not like you need to be up to date at tech or ideas at all times to do anything about the weaklings there. Most importantly, regions like India and China has a huge potential for economic growth just using trade and manufactures, making a cash-focused playthrough there skyrocket until you can abuse advisors freely to quickly catch up.
In general, I just don't lack in monarch points, even when creating Europe-sized empires. And I have only twice in all my EU4 history taken admin. If I want it, it's due to the state limit, not the unnecessary coring cost reduction. There's an opportunity cost in not taking another idea group. In the short term, other groups are just better. And short term brings long term wealth from my experience.