See Sunlit Portal and Sweltering Portal.

Reduce these out and ramp more for artifact decks? I like this concept a lot. This is maybe harder than Sunlit Portal though? Idk, my choice would be using "draw second during a turn." I'm kind of just biased against scry I think and I could be wrong, but I feel like scry only shows up a couple cards each set while the lifegain feels much more common.

Sure, that's sensible.

My main question is: is it bad that these do nothing until triggered?

In today's era, probably not. Going from the "cast a land aspect," maybe some kind of small boon that is generic enough for artifacts that it could appear on each of the (presumably) five (or maybe six) cards of the cycle so that a player could at least do something with if they're stuck on the trigger to flip it.