At the moment I use my FDM printers for everything.  FDM works great for nice sturdy parts to build up on.  With a 0.2mm nozzle and using 0.05 layer thickness I can get very nice detail.  SLA is really good for details and does a much better job on surface quality for smoothness but is not structurally as strong in my experience.

As for mixing the two I would use the FDM for the basic structure, working parts and major details and the SLA for fine surface parts and intricate details.  I am considering doing some "photo etch" like details with my FDM printers to see if the technique works.

For what you are doing I think you will be very pleased with SLA.