Easiest option would be to use more geometry on the other half and match the number of loops. It'll save you a lot more time not trying to reduce geometry that doesn't need to be reduced. You can also merge the miss matched edges on that flat shelf between the 2 parts using an edge loop going around in the middle.
Thanks, that really helps clear things up, the approach you described is a lot easier than linking a quad sphere. I tried that after your first response and while it achieved the results, it was very limited (for instance, in the actua model i'm copying, since the cylinder is conical, that means the hemisphere needs to…