Best Sealant for a Plywood "Floor"?

Atypical but perhaps interesting project here:

I'm looking for the best way to refinish 3/4 birch plywood that is being used as a dance floor (barefoot dancing, no shoes).
Should I continue with Thompson's Water Seal since it worked for me last year, or upgrade to something better/more professional? My biggest concern is the feel of the finish as it will be in direct contact with dancer's skin: we want a smooth surface that is neither sticky nor slick. I do not nead the longevity of a traditional deck as we're talking plywood here. But I would like to make it through another year or ideally two.

Additional factors:

• Will tinted sealers change the feel of the finish? the wood is significantly faded so I would    like to add a bit of color, perhaps a semi-transparent. However I prefer the natural grain look and don't want the roughness of paint.
• I need a product that allows for quick application over the course of a 1-4 weekend days max. Its rainy spring where I live so the number of workable weekends is unpredictable. Its also 

Last year I used Thompsons Water Seal and found that it left the wood feeling as natural as possible, but it was oily in the initial days after application and the wood seemed to soak up dust and dirt. This year, I've thoroughly cleaned it using deck cleaner and am ready to re-seal. 

Last year I built a 16 x 8 dance floor on my apartment building's rooftop using 3/4 in birch plywood. I used furniture grade ply (yes i know this is better for interior projects) that was already extremely smooth to the touch, laid on top of simple wood joists. We sealed the edges using wood glue, and finished with one coat of Thompson's Water Seal. The floor is exposed to the elements only when it is being used, and the rest of the time is covered in a tarp. However a few of the boards on the edges did sustain some water damage and began to delaminate from seepage under the tarp. Those boards i've either replaced or the ones with minimal damage I fixed with woodglue and clamps. At the time it was a temporary experimental project, that we hoped would last one summer season, so the goal was cheap, easy. Try something and see if it works. 

The results were, it worked! We had a wonderful surface which I used from May-September as a personal studio and a stage for performances. With the success of the initial project I want this to continue so I'm willing to invest a little more in finishing the floor. 

photos of the project can be seen in the Spontaneous Combustion gallery:  https://www.sarahchien.com/gather

It seams like a dance floor is inbetween a deck and a piece of furniture- the wood surface needs to be much smoother than a traditional deck, but it isn't an interior surface. Spar Varnishes, for example say they are not to be used on "high traffic areas like floors", but I don't need the durability of deck sealers that are trying to preserve a part of a house which will be exposed to all weather.