I can only give you my own view, hope this helps in deciding.
I chose the F-5 for nostalgic reasons and for now i will not buy any ww2 related planes for DCS.
When it comes to ww2, i stick with il-2.
I generally like a bit of "older" planes of days gone by. Our airforce had the NF-5 (a modified F-5) during the 70's/80's and this also adds to my nostalgia.
The relative simplicity of the plane also spoke to me, the cockpit is much simpler than let's say an F-16. As a family dad, i didn't want to spend too much time learning the cockpit from scratch.
The cockpit has quite good visibility allround.
The graphics, you say they are not so good, i don't agree with that. But then again, this is not my focal point, i think im not so demanding here.
Last thing, but not least, the F-5 is a bit of a niche plane to me, it is not so common in flightsims as an F-15 for example.