Until it gets below +5 C, I wear shorts. Below 5, leggings. Below -5, or with some serious wind chill, then I pop out the winter leggings.
At 10 C, I go from tshirt to long sleeved tech top. At below 5, I might go back to a racer back style tech top with a thin merino layer over it (keeps me warm but wicks well). If it’s windy, a thin windproof jacket. As it gets colder, or if it’s a relaxed recovery run, then at 5 C might have a long sleeved plus jacket (invariably end up removing the jacket and it gets tied around my waist).
Thin merino gloves until deep winter when it’s thin gloves plus mitts on top (-10 and below). I hate hats with a passion so use a headband to keep my ears warm. A buff or neck scarf (thin and light merino wool…. yup, it’s my favourite).
Socks - merino but with different weights so light in the spring to autumn, heavier as it cools down. Runners - I have a mix from the regular to one pair with goretex for rain and mud, and full on winterized shoes for the ice and snow (winter at -30 C).
I’d say slowly add on kit as you need it and think of layering or how to mix and match it. My wardrobe is - shorts, leggings, winter leggings, vest tops, tshirts, long sleeved tops, thin merino long sleeved top, windproof running jacket, running jacket (side panels to allow for breathing, vents), mix of socks, different running shoes, headband, gloves, mitts. I have built this up slowly over the last 3-4 years and love a good sale to keep it affordable. Thrifting is also a good way to do this but requires a bit of dedication.
So my wardrobe is a mix and match, adjusting to the weather.
Re evening running - reflective elements on clothing are good but lights etc are better. Think of placement and whether a light source varies eg flashing. You can buy clip on lights, headlamps (handy if route is not well lit), ones that go on ankles or upper arms, to ones which are on a harness. It’s taken me a while but I’ve settled for a light harness which I pop over my clothing. I finally came round after watching other runners. If using clips or say an arm one, think of where to place so it reflects your movement rather than being a static point. More likely to be seen.
I’d also recommend a waist belt with water bottles or similar. Hydration is important and cooler weather does not reduce the need to keep hydrated.
And yes, merino well gets wet but, as long as you are moving and generating heat, it will keep you warm. Might rethink that if it’s absolutely bucketing it down.