My bodyweight is now 140lbs, up from 135 when I was just rowing. So I've gained about 5 lbs of muscle (well weight at least) in the last 5 months, although the last couple months it's remained the same.

I'm thinking maybe this is just my ideal natural weight?

I'm not looking to add size or bulk. Ideally I'd love to start to resemble a boxer's body, muscular but lean. I guess training 3 hours a week probably isn't going to produce that, but if I could look in shape, so I at least look like I work out, that would be great.

I don't think I llok like that yet, but I look much much better than I did at the start of the year.