All good suggestions. A couple more thoughts....
- re meats: super lean meats like pork loin are probably going to be dry no matter what you do
- re other meats, the directions usually say not to add any water at all, it is only a flavor option
- stew and sauces really should not dry out
So I wonder if your lid is too loose:
- when (as usual) I was doing an exhaustive search for the best crock pot a couple of years ago, I do think I remember some reviews commenting on the fit (or not) of lids, you might do a Google query for your make/model to see if loose lids are a complaint. I remember complaints regarding fit, not flat, lid too light, etc.
I should also add for anyone following this thread later who might want to purchase a newer crockpot, the best reviews that I found were for CrockPot brand. We got the SCVT650-PS-Programmable-Touchscreen-Stainless although now I would get the travel model which has handles that will fold over the lid. Yes, it's large for two, but the oval size allows you to put in a wide variety of meat sizes (including the best ribs that you'll every eat).
- The reason I went with CrockPot is that they had by far the fewest complaints regarding crocks cracking during cooking as well as length of life. Some mfgrs had an absurd (at that time) amount of complaints where the crock made an explosive sound when the crock cracked, ruining the food, about 1/2hr or more into the cooking cycle, and no, most were not frozen food put in the crock. Many people were on their third replacement. The consensus was that the crockery was inferior either in material or when it was fired. Complaints were ongoing over several years so no fix in sight (at that time). I don't remember the companies so I won't say here, although I remember that they were high end. If you Google the brand you are looking at and crock cracking, you'll get the info you need.
Oh, one more thing, make sure that your company does offer replacement lids and crocks for simple accidents like dropping and they don't cost as much as a new unit.