If you need to bulk up two weights above your heaviest interpolated weight, it can be quicker to export the boldest instance, create your heaviest weight then use FontLab's blend tool to generate the intermediate weight and then manually clean up the mess. That way you're free of the restraints of whatever mechanisms were necessary to interpolate to the lightest weight.
I think some glyphs are quirky and fun and others look plain and staid. If this were my project, I'd scrap the lowercase. The lowercase doesn't make a lick of sense. I like BDGKNRSTUZ. If you make the other letters match that style, you'll end up with an amusing version of a Federal Reserve Bank Note type of idea. The flip thing you're doing with the O isn't working. Q's tail doesn't have the same personality as the mustache stroke on the R. You need to spend more time on the 8...look at some examples of the style you're modeling this on for ideas.
I don't think there's anything inherently bad about either platform; it's just not for everyone. I remember in 1985 when I tried a Mac...I just didn't connect with it and took the Amiga path to Windows. I don't want to derail this thread with a Mac/PC fight but it's frustrating to see all the good font tools coming out on the Mac while I'm struggling with Fontlab in Windows.