I had ridden an XR75 for a few years when I was a kid, but then nothing until middle age when I bought a used CRL250L with 375 miles on it and I got my license. That will be four years ago in July. The first year I had it I mainly commuted with it on pavement. 10 miles each way through the suburbs. Speed limits of 30-40mph. At the end of my second summer with it I bought a used NC700XD because I wanted something I could take on the highway. End of last year I also purchased an Africa Twin. I now have almost 5,000 miles on the 250L. I tell you all of this so get at least get a partial sense of how long I have been riding and what I do with the bike. Your skill level, expectations and what you want to do with it could be something completely different.
Personally I don't like riding the 250 much over 60mph or on the highway. Its too light and working too hard for me to be comfortable on it. If you go on Thumper Talk you will see people saying they commute 30 miles one way on the freeway and it "will do 75 all day long". I don't think mine will do that, but mine is all stock except for the addition of a tachometer. Maybe a modified 250 would do better. I wouldn't go far on the freeway with it. I have done a couple of groups rides (20-40 people) on a mix of highway and gravel road with folks who were mostly on larger adventure bikes or 650 singles and I couldn't keep up much of the time.
Last year I had the 250 on some off-highway trails for a few days and I really had a lot of fun with it. I am guessing maybe that was 100 miles of riding. My off road riding skills are what I would call novice. I would love to do more of that with it but its hard to find the time.
My biggest disappointment with the 250 is the power. I know I could do a bunch of tweaks with exhaust, a fuel controller, sprockets and airbox mods to get a few more HP but I don't think it would be worth it to me. I don't want to me modding and wrenching all the time. I just want to ride. In my opinion the bike is what it is. If that isn't enough for me then I would just as soon get something else than try to turn it into something different. The other thing I wish it had was more fuel capacity. Other than the HP I often hear of others complain about the seat being too firm and the suspension too soft for serious off road riding. I would agree that the seat is firm but it doesn't bother me much. Not for rides of a few hours or less. In my opinion the bike is easy to maintain and I feel it handles well for me on and off road. Overall I am pretty happy with it.
Would I but the CRF250L again? I'm not sure. When I heard the CRF450L was coming later this year I got all excited and had to check it out right away. I had been hoping for something like that for quite a while like many others. I guess I want to know more about the service intervals its going to have. If they are vastly different than the 250L then it may not be what I want. This bike might be more dirt biased as you say than I need. Also the point about the fuel tank being the same size as the 250L or just slightly smaller is actually kind of a big deal to me. I will wait and see what people have to say about it after its out. The other bike I might look at in place of the CRF250L would be the DR-Z400S from Suzuki. After rambling on with all that, I suspect I will have the 250L for quite a long time yet.