Only you can decide. I have a beard every winter since retiring from the military (mostly Army National Guard). I shave my neck and the top of my cheeks. I like it this way in the winter, but love having a change come Spring.
That’s one of the hardest things for noob orangutans... I mean beard growers lol! Learning how to trim em.
I say you’re half way there, keep it going if it’s not driving you crazy. You might like it, you might hate it, but you’ll never know if you don’t try. And let’s face it, it’s the new Covid inspired look. No one is going to call you out on it looking dirty or whatever people say about beards. So now is the time.
Your hair color is awesome and deserves to be displayed to its full shining glory. The upper moustache hairs will grow longer, providing even more fulness to the moustache. The beard shows good fullness in certain areas. I would trim to shave off the less full parts. Maybe a Van Dyke style on the lip and chin. Sharp anchor edges on the chin, or rounded around the chin line, . . .
Looks good at 4 weeks. If you have the patience, try 4 more and get a good idea of what the full potential is.
You've got a month's start, keep growing it. What many don't realize is the time it takes to grow a beard &/or mustache. Give it at least another month before you decide. Better yet, give it two more months!
I also think that four weeks is not enough time. That said, you may be a little too light at your current age to pull off the full beard look. Maybe another style would suit you better.