There are a variety of good kibbles out there that would be a complete diet without adding any tinned meat.
What to feed often comes down to personal choice, metered by personal budget and availability...
Generally avoid foods with artificial additives (like Bakers, Pedigree etc) as the additives have been associated with hyperactive behaviour. Look for a food which gives a named protein source as it's main ingredient (so, for example, "chicken" rather than "animal derivatives"), and has as few unnecessary fillers as possible.
Some highly recommended brands include Burns, Healthy Paws and Orijen.... though there are many others. We fed James Wellbeloved when we fed kibble (we do a raw diet now). Harringtons is a good option if you are on a tighter budget, and is sold in many supermarkets.
While a few human food treats aren't a problem, I probably wouldn't recommend a whole sausage as an extra - you could cook her one, cut it up into tiny pieces and use it as training rewards if you want. But a whole sausage, as an extra to her normal food and training rewards, could set her up to put on excess weight...