turbocharged motors don't require BOVs, especially ball bearing units, people have been sold on that idea for whatever reason. Even if you decide to use one you should recirc it to the intake path before the turbo if the MAF is metering ahead of the turbo (similar to most stock recirc setups). A lot of superchargers use their own oil system which is somewhat convenient from an install perspective. Though on an e36 M3 you need to take the oil pan off anyway and check the oil pump nut (which I still haven't done) so it's a good time to plumb a return line bung. Engine management and fuel management have to deal with the same issues on both. I tend to prefer turbos, they are easier to deal with (for me) but that is because I'm just used to working around them.
Neither are really that complicated, it is more a matter of preference. On my car though I think I'd be happy with a set of cams, injectors (bought), HFM, different chip, Kromer Kraft headers and exhaust.