I typically leave it default and I have seen this same thing in CMBN and CMFI as well. I have changed parameters with little effect. I wonder if the code collects all the maps that meet the parameters (Say Small-Open-Meeting) and then only picks the first one on that list or that list only contains one map due to the map collection code not working well with the map naming convention. A quick survey through the RT quick battle map names shows there is only 1 Small Open Meeting map by name : Open Rough Meet 036. That is the map I keep getting when I ask for Small-Open-Meeting so maybe there is something with the number of maps available with my battle parameters.
A quick survey of the CMFI quick battle map directory shows again 1 map for Small Open Meeting... I think that must be the problem. Only a short list of maps for Size Terrain Engagement type. 40 maps for Meeting Engagement in CMFI. Reduce that number for terrain and size and it makes sense that I am seeing the same maps.
OK. Now that I think I understand it I can move on or make some more Quick Battle maps for my needs...
Bobo