Without seeing your house, I'd suggest trying a deep cranberry color. It is just paint on something that's already painted. :) Just an FYI: my porch was grey and I over-painted w/ Colonial Blue and it made it look much better to me. A few years ago I was able to have the old/bad porch floor ripped out and I had it replaced with new natural fir. The finish I applied was marked "natural" so I expected it to be clear, but it contained stain with a barely reddish-golden-brown tint to it. What's interesting to me is the difference in the color of the room that looks out onto the porch!!! the blue porch floor reflected a cool light color into the room... the new stained wood porch floor reflects a very warm yellow-red color into the room -- like it glows. It makes the room look so different! You might want to think about the color you'd like reflected into the rooms that overlook the porch. :)

if you like the vinyl, I say go with it,

I've seen the Varathane "Crystal Clear" used over cork flooring and it does a very good job for the price point. And to be clear, $60/gallon for FLOORING polyurethane is DEATHLY CHEAP. Any cheaper and you are purchasing nothing but headache (with all the odours that go with oil based finishes). Remember: you have a VERY flexible floor (sheet vinyl is one of the MOST FLEXIBLE floors we have (carpet is #1). That means you NEED to have a FLOOR FINISH that can HANDLE the flex. And that is SUPER hard to find for anything UNDER $150/gallon (Loba WS Easy Finish is one of the them). You NEED flex. The Varathane is a little brittle...but if it is good enough for CORK (which is the 3rd most flexible floor) then it will be good enough for your project. It is tough and it is a FLOOR FINISH. The "other stuff" isn't floor finish. Which means it is NOT tough enough for floors. Anything that is "furniture" grade of cabinetry grade is more watery. You are paying for water...not polyurethane. And those finishes often need 5-7 coats on furniture. You would be finishing your floor sometime around Christmas. And the "4 coats" for the Varathane is for RAW WOOD! Not a floor such as yours. I would be surprised if you needed more than 2 coats. I've seen it used on factory finished cork, and we suggested 2 COATS. Why? Because the third coat made it TOO BRITTLE. So my thought is the paint is going to be like the primer...or the first few coats. The Varathane can go down in 2 coats. You can apply the Varathane (two coats) in one day. It has a full cure in 7 days. I would leave it alone after 2 coats. If you feel you are not getting the wear you were hoping for, you are welcome to apply another coat at a later date. And in Canada, we have access to 1 litre (quart) cans of the Varathane Nano Defense for about $30/can. It is a great product that can be found off the shelf. https://www.rustoleum.ca/product-catalog/consumer-brands/varathane/water-based-clear-finishes/nano-defence-premium-clear-floor-finish/  The Varathane Diamond was the precursor to the Nano Defense. The base components are very similar. The Nano Defense is tougher...it has aluminum oxide particles suspended in it. And 2 coats is ALL you need. That's for sure.

The floor likely has a 'wear layer' of UV cured very hard aluminum oxide clear from 12 to 20+mil thick. You will need to sand the finish to get the next coat to adhere. That coat(s) would be a primer. And then multiple coats of a topcoat. I'd guess at a roller applied boat paint. It's meant for this type of application. Kinda self-leveling. You must use products by the same manufacturer. And follow the recommended procedures. Perfection Pro topside paint by Interlux. A lot of work and the products are expensive. . . .It will not be as durable as the original finish because it will not be as thick. . . .So you may want to pull up the flooring and replace it with a rigid vinyl plank that you like the look of.