These are pretty nice, you seem to have gotten a good handle on RobA's tutorial.

*temporary soapbox mounting*
The whole lightness/darkness issue of maps is a bit subjective I think. I have often stated that many of Ascension's maps seem dark to me - but this is easily fixed by simple adding a layer of white set to 'Soft Light' at the top, the reverse can also be done for maps that seem overly bright.
*temporary soapbox dismount*