Yep. I also deglaze the pan with whatever wine/stock/tomatoes I'm using before reducing it as it doesn't reduce in the slow cooker in the same way it would on a hob or in the oven.
I wouldn't bother personally. The only thing it's essential for IMO is mince. Slow cookers are brilliant, for everything from pot roasts & curries to home made chocolate fudge Thousands of recipes online.