Yeah, finish first, then decide.
I've found that halfway through a book I'll suddenly notice a trend, something that I want to continue at all costs, and it's usually something that only works with half of what's gone before it - so you edit the rest.
If you wind up with an ending that you love, and it's actually the subplot that made you jump with joy, then chances are you'll need to change a lot around (subtly, often) to make it all click.
I've been trying to add extra description or inner thoughts to my current WIP, because my previous books were all lacking in that somewhat... I'm not a descriptive person, and don't like a lot of it in the books I'm reading. Like, if someone hits themselves with a whip, I don't care what the ritual is called and I certainly don't care what type of whip it is by name at least - a simple "it had nine tongues with studs" will do, and then "it was meant to be a cleansing through pain" - none of this "The ancient Jerkwads used this practice for 1000 years and it was called X and blah blah blah." Just a pet peeve of mine.
But the point of my trying to write extra description is that some of it will be necessary, so even though I'll chop most of it out in the end, at least some good bits survive, which for some readers would be essential.
Basically, more is better if only for the fact that you can then edit freely and be merciless with what gets the chop.
But back to my original point - leave the scene in until you're done writing the whole story. You said you've got a follow-up scene, which is something you're preferring due to the daylight thing. Definitely keep that, and then later you can probably make a better decision.
And as always, back up your work, every last word of it - if you start editing, keep an original copy, etc etc.