I'm aware of all that - this is the fifth house that I've redecorated. I just need some breadcrumbs to point me in this new direction of darker trim, lighter walls.

The selection of paint for the walls cannot be accomplished without seeing the flooring and the other general finishes in the room. Do you have existing furnishings that will be used in the rooms. Those will have an effect on the decision.

Post images of the room for the best suggestions.

I would paint the walls the same color as the trim.

The floors are medium stained wood. Furniture is traditional, warm tones, mostly neutral. On the moving truck so no photos.

Like I said, I really can fill in the rest of the puzzle pieces myself, I just need someone to to help me find one or two edge pieces.

Here is a photo of the mudroom, no lights on, mid morning. Lots of trees around so the house is dark.

If you really want to mix it up look at Sea Salt....a fresh look throughout that goes with neutrals and wood tones.

This room is Dover White and Sea Salt using SW ColorSnap. The LRV 63 so it is a good wall shade. You could try cutting the tint by 25- 50% for something lighter and brigher.

Keep in mind lighting can make it look bluer or greener.

Topsail is a nice Blue LRV 75:

I like the paint colors that are existing.

Beverly, as mentioned in the OP, the wall color reads muddy to me. I think it's more apparent in the mudroom photo. YMMV.

Dover White has a good splash of yellow, making it cleaner, creamier than most of the other whites. If you want white walls, use the same white. (Have the store do a color match of your trim color, as it doesn't look like a dead ringer for Dover White).

It won't play well with lighter, brighter whites.

It may work really nicely with a cleaner neutral color that isn't as dark or muddy as your current wall color.

Here are a few colors I would test with your trim. They will also need to work with the floors, which may get a bit tricky.