Advice on choosing a hair color that suits me!

Hi, this is my first post here! I am a natural dirty blonde/strawberry-ish blonde. My natural hair grows in darker at the roots, lightens in the sun, but also looks reddish in the sun. I have only ever been blonde and usually have highlights added to keep it looking blonder and lighter. I have recently decided that I want to go darker. It's something I plan on maintaining for quite a while. There are only about five people (including me) in my entire family (both sides) that are natural blondes, everyone else has light to dark brunette hair. I have green-hazel eyes with some brown/gold flecks and I have freckles. I've tried finding my skin's undertone by looking at my veins I see blue and purple veins, I do seem to have a pink undertone, but I can tan. (Honestly some of the information I've found so far on undertones has been confusing and often contradicting to other posts). However, I look good in neutral, Earthy, and jewel tones. I usually go for navy, black, grey, burgundy, maroon, olive green, deep green, etc colors for clothes.
I've been so obsessed with my undertone because I really want to ensure that the color I dye my hair will look good on me. I plan on going to Sally's Beauty to buy my hair dye. I was thinking either Ion brand or One n Only's Argan Oil dye. I am definitely open to suggestions.
NOW to the color! I originally fell in love with the cherry coke hair color, but as I began exploring I also fell in love with burgundy and violet colored hair. I think I've narrowed it down to 2-3 different ideas!
---The first is a collage, the left picture is mainly just to show my eye color and skintone/undertone. The second shows my natural color with highlights that I had done in February. I haven't had my hair colored since then.
I found these on Pinterest:
---The second attached picture is one of the shades I am considering. I think this is similar to Merlot.
---The third is another shade I am considering and it is one of my favorites. The post said that she mixed 5rv with 4rv.
---The fourth attachment shows a much darker shade, but I'm loving the plum/violet that shows through.

I'm having trouble deciding which will look best on me! Like I said, I plan to maintain this color for a while. I think my biggest concern is when I'm out in the sun my hair will appear ultra-bright! I also don't want to choose a color that will wash me out too much or clash with my skin?!

This is my first time mixing dyes, so I'm also looking for advice on how to mix to get the shade I want. I plan on using a 10 developer.

My main questions are:
1)Which color would look best on me and help bring out my features?
2)How do I know which dyes to mix together? I'm assuming the 5rv+4rv will give me more red than violet?
3)I plan on doing a strand test, but if I mix the dye beforehand and do the test will the dye sitting get stronger in color?

I guess that is technically four questions!  😀

I'm so excited to really change up my look! I've only ever been on the blonde spectrum, but I am ready to go to the dark(er) side!  😉 It's just making the final decision on the color!