Challenge and metaverse points are two completely different beasts.
End of quote
True, but they are not mutually exclusive. Completely ignoring points considerations is not healthy for your Meta ranking, but completely ignoring challenge and variety may not be healthy for your fun factor. For me, the latter is a lot more urgent.
I admit to using Populist party more than any other, but that still only covers about a fourth of my games. I have taken high diplo picks only a few times. Yet I'm still on the front page in the Meta ranking.
Cranking some 30k and 35k wins on Medium and Large maps can actually keep my score moving along as fast as doing gigantics but fewer of them. And I will vary the habitability, too. On Rare maps, trade picks and party give a stronger relative boost. On Abundant maps, economic bonuses may help more. On Gigantic, +2 speed may be worth more than high diplomacy. On small maps, War Party may help you crank those early game wars, with Battle Hammers or even occasionally with Vettes. And an influence emphasis can help go for a quick cultural win.
The diplo picks are definitely the strongest ones in the game, but the +5 PQ pick is up there, too, and I admit to selecting that one for over half my games.
If you are enjoying the game more, you play more, thus score more. Cranking points with the easiest/fastest set of options may help in the short term, but can you keep it up for the long haul? Because RB is not likely to run out of steam.

We're still picking up momentum, actually, as we got a late start at this game and our players are still learning the ropes.
- Sirian