New to themes...

I'm not much of a theme person at all but I do recall loving the L theme for my 8320 Curve. I currently have a 9700 and would like a simple L theme with a spot in the upper right for weather. I'll most likely be purchasing BerryWeather so I don't know if that makes any difference. In any case, I can't seem to find a very clean and super basic L theme that doesn't change much of the original Precision Zen theme that came with the phone and that I like. I'd like to see if I can just work on this on my own and I guess I'm just asking how hard this might be to tackle knowing that the only changes I'd like are the L configuration and the weather icons showing on the upper right. Maybe I'll go as far as change the default menu highlight color (currently blue) but that's about it.
Any input will be greatly appreciated.

Thanks.