Natural hickory flooring generally has quite a range of tones, a lot of movement and is visually busy unless you are using an engineered version that is somewhat more consistent and quieter. You don't want 2 large areas competing with each other so I'd keep the ceiling as quiet visually as possible.

What is the wood species of the ceiling? That's going to determine how easy/difficult it will be to pick up a tone in the floor. Is this ceiling installed or are you (hopefully) planning to do the stain and finish prior to installation,, in either case making test samples on ceiling scrap is important. Remember what it looks like when you hold it next to the floor is not what it will look like high over your head. You need to see all the major color players in your space in the plane that they will be installed and at the distance they will be from each other. Which leads to wall and trim color. Presumably there will be paint on the walls between the floor and ceiling and that, too will impact how the two wood tones relate to each other.

Maybe keep the feature all white?

Out of those four options I'd lean towards the medium one (second from the right). The lighter ones are too close of a match. Definitely not the grey. That wouldn't bring any warmth in and it would clash with the hickory flooring. I do think an all white would be beautiful too though.

All white. Much too busy otherwise.

Any chance Synergy offers a whitewashed version of a stain close to your floor color? If you only have the choices you've shown here, I'd say the second from right probably ties in best with your floor. But since your ceiling will be quite dark with it, I'd keep the wall color a soft white to brighten the space and not try to mix in another color along with the floor and ceiling.

All white. You are dangerously close to visual overload with so many complex details and such a busy floor.

Lets

To make things easier let's get all your options in one place. I clipped the colors available from Synergy in both Southern and Ponderosa Pine.

Here's your floor and the 4 options you narrowed to originally

Here's all the Ponderosa Pine options

Here are all the Southern Yellow Pine options

And here's my opinion. You'll either have too much going on with a visually busy floor, visually busy ceiling that's cut up with visually busy beams or you'll have a compete disconnect between your floor color and ceiling color. Or both. Probably both. Assuming the floor is a done deal and not subject to change at this point, I honestly don't see a good option for you for the ceiling from Synergy. Perhaps someone else will see it differently and recommend something for you from these choices.

I like the clear stain the best for the ceiling. Or a white wash that isn't a stark white.

No weathered grey. It won't go well with the warm toned floors and it doesnt look like it goes with the style of your home at all.

Ditto - no weathered gray - you are introducing too many elements that you (or your husband) like individually but that don't relate well to each other. It's going to overwhelm the senses and feel disjointed. In the picture you posted of your ceiling beams, there is some unfinished Wonderboard visible - guessing that's for a fireplace wall? What's going there?

I would be more comfortable with drywall up there over the old wood ceiling and the EPS foam insulation. Drywall is Class I whereas the pine that you're proposing is a Class 3 fire resistant material.

Too many clowns already in the circus ring. Stop while you are ahead and just keep it all white. ci_lantro is correct that drywall first would have been the better choice.

Are you tied to using Synergy choices? Is it possible to find another supplier that can provide a wood matching the lightest tone in your floor since you don't want white?

Among the choices you posted, I would go with the clear Ponderosa Pine you posted above for the ceiling. This latest sample of your floor looks to be a different tone than the first one you posted.

I think the rustic white is much more compatible with your floor than the other choices.

You're talking about the lower, small picture that appears to have a lot of texture?

First let me ask - have you seen the hickory actually installed in a space or are you going by the small picture from that website when you say it's not as busy as the clear natural? I can see large color variation in just that tiny pic so do not trust that it's not a busy floor. From the website in the gallery section here is a pic of the floor you think isn't as busy. That's a lot of color variation.

Now how do you like it with your rustic white? And again, What is going up on the wall with the wonderboard? Stone? Brick?

Tammy based on the ceiling beam detail and the tall fireplace wall it appears you have a large lovely room you're working on and I'll go out on a limb here and assume you have a reasonable budget for these changes. You don't know me but trust me I never make this suggestion - Do yourself a favor and put part of that budget to hiring some design help to be there in your space with you. Without an overall direction you are headed for trouble based on the wildly varying materials you are dealing with just on this thread and none of us have a clue what type of furnishings you have or want to buy for this space. It would really be a shame to get to the end of this project, look at your space and not have it look and feel the way you want - you'll be standing there scratching your head wondering why you don't love it when you love the floor and love the fireplace stone and love the beams and love the ceiling but don't love them all together.

It's helpful to see the three elements together as you've posted because--just IMO--it shows the disparity between the warm, golden tones in your floor and the grey, ashy tones in the ceiling. There's no cohesion in the design.

How about some info and pictures of the entire space. How big is this space? Dimensions? Floor plan and how it relates to adjacent spaces and will they have the same flooring? What is this room used for? What type of furnishings do you have for it or intend to buy? Will this room have a rug? Curtains? You'll get better help with more info.

What are your kitchen cabinets? That's another significant wood element that has to be considered in this visual mix and they are a done deal so they become the boss - everything needs to work with them.

And your wood flooring is going to run into the kitchen?

Yikes! Sounds like everything I've picked isn't working. I hope to meet with designer next week. Can it be saved? Lol? ;o)

Once: You'll either have too much going on with a visually busy floor, visually busy ceiling that's cut up with visually busy beams or you'll have a compete disconnect between your floor color and ceiling color. Or both. Probably both.

Twice: you are introducing too many elements that you (or your husband) like individually but that don't relate well to each other. It's going to overwhelm the senses and feel disjointed.

Seems the third time was the charm: You are stuck in the unfortunate spot of selecting things that appeal to you individually, but that do not at all work well together. You need some big picture help.

Your cabinets are installed. That is your basis for everything else. In the pictures they do not look like the color from the mfg website that you showed but that's not surprising. Regardless, they are lovely. Your counter choice is beautiful but look here.... do you see what's happening? These are pictures on monitors where colors are never true, not real life but this is the beginning of trouble. and not inexpensive I can fix it with a coat of paint trouble. That stone is costly - are you obligated to it? Wait for your designer next week. I'd recommend totally stepping away from this and stop trying to come up with *the thing* that's going to tie this all together. Hopefully the only thing that's a done deal is the cabinets and if anything else is pending, stop it while you can.